Journal articles: 'High Performance liquid chromatography coupled with mass spectrometry (LC-MS)'

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Neuhof, Torsten, Robert Köppen, Matthias Koch, and Irene Nehls. "Letter: High-Performance Liquid Chromatography/Electrospray Mass Spectrometry Analysis of the Mycotoxin Aurofusarin." European Journal of Mass Spectrometry 14, no. 5 (April 1, 2008): 329–33. http://dx.doi.org/10.1255/ejms.935.

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High-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) can be used for simultaneous quantification of various mycotoxins in contaminated food samples. Therefore, multi-mycotoxin methods have been developed in the last couple of years. To enlarge these methods for further analytes, we have developed a LC-MS/MS method for the quantification of the mycotoxin aurofusarin. Additionally, further LC-MS n experiments were performed to demonstrate the fragmentation pattern of aurofusarin. Applicable multiple reaction monitoring (MRM) transitions of aurofusarin were found and optimized by parameter variation of the tandem mass spectrometer. The applicability of the developed method was tested by analysis of naturally contaminated wheat.

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Zhang, Feng, Mingping La, Xiaobin Gong, Shouhong Gao, Zhijun Wu, Lianna Sun, Xia Tao, and Wansheng Chen. "Metabolite identification and pharmacokinetic study of Lamiophlomis rotata in rats." RSC Advances 6, no. 29 (2016): 24331–39. http://dx.doi.org/10.1039/c5ra25264d.

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An ultra-high performance liquid chromatography coupled with time-of-flight mass spectrometry technique and a subsequent LC-MS/MS method were developed for metabolite profile study of Lamiophlomis rotata extract after its oral administration.

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Gao, Mengyuan, Xiaohua Jia, Xuhua Huang, Wei Wang, Guangzhe Yao, Yanxu Chang, Huizi Ouyang, Tianxiang Li, and Jun He. "Correlation between Quality and Geographical Origins of Cortex Periplocae, Based on the Qualitative and Quantitative Determination of Chemical Markers Combined with Chemical Pattern Recognition." Molecules 24, no. 19 (October 8, 2019): 3621. http://dx.doi.org/10.3390/molecules24193621.

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Quality assessment of Cortex Periplocae remains a challenge, due to its complex chemical profile. This study aims to investigate the chemical components of Cortex Periplocae, including its non-volatile and volatile constituents, via liquid chromatograph–mass spectrometry (LC-MS/MS) and gas chromatography–mass spectrometry (GC-MS) assays. The established strategy manifested that Cortex Periplocae from different producing areas was determined by identifying 27 chemical markers with ultra-high-performance liquid chromatography, coupled with quadrupole tandem time-of-flight mass spectrometry (UPLC-Q-TOF-MS/MS), including four main groups of cardiac glycosides, organic acids, aldehydes, and oligosaccharides. These groups’ variable importance in the projection (VIP) were greater than 1. Simultaneously, the samples were divided into four categories, combined with multivariate statistical analysis. In addition, in order to further understand the difference in the content of samples from different producing areas, nine chemical markers of Cortex Periplocae from 14 different producing areas were determined by high performance liquid chromatography coupled with mass spectrometry (HPLC-MS/MS), and results indicated that the main effective constituents of Cortex Periplocae varied with places of origin. Furthermore, in GC-MS analysis, samples were divided into three groups with multivariate statistical analysis; in addition, 22 differential components whose VIP were greater than 1 were identified, which were principally volatile oils and fatty acids. Finally, the relative contents of seven main volatile constituents were obtained, which varied extremely with the producing areas. The results showed that the LC-MS/MS and GC-MS assays, combined with multivariate statistical analysis for Cortex Periplocae, provided a comprehensive and effective means for its quality evaluation.

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Sosa-Ferrera, Zoraida, Cristina Mahugo-Santana, and José Juan Santana-Rodríguez. "New Developments in Liquid Chromatography Mass Spectrometry for the Determination of Micropollutants." Chromatography Research International 2012 (December 17, 2012): 1–18. http://dx.doi.org/10.1155/2012/748989.

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The combination of liquid chromatography (LC) with mass spectrometry (MS) in the environmental field has appeared as a valuable tool for the determination of micropollutants. Several groups of compounds have been considered as particularly relevant (e.g., pharmaceuticals, hormones and other endocrine-disrupting, personal care products and their metabolites, flame retardants, surfactants, and plasticizers, among others) since the same ones are continuously being released in the environment mainly as a result of the manufacturing processes, the disposal of unused or expired products, and the excreta. Because these micropollutants are not completely removed in the environment, very specific and sensitive analytical procedures are needed for their identification and quantification. High performance liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) (or LC-MS2) and especially time-of-flight mass spectrometry (TOF/MS), has allowed that many environmental contaminants that are highly polar or nonvolatile or have a high molecular weight to be analyzed or identified. In this work we present an overview focused on the developments of liquid chromatography mass spectrometry applied to the analysis of the main classes of micropollutants in aqueous and solid environmental samples. Various aspects of methodologies based on these techniques, including sample preparation (extraction/preconcentration) and matrix effects, are discussed.

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Roy, Shikha M. N., Kiran V. Mangaonkar, Santosh M. Yetal, and Santosh S. Joshi. "LC-MS-MS Method for Determination of Metolazone in Human Plasma." E-Journal of Chemistry 5, no. 3 (2008): 634–40. http://dx.doi.org/10.1155/2008/425974.

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A rapid, sensitive and specific method for quantification of metolazone in human plasma using metaxalone as internal standard is described. Sample preparation involved a simple liquid-liquid extraction procedure. The extract was analyzed by high performance liquid chromatography coupled to electrospray tandem mass spectrometry (LC–MS–MS). Chromatography was performed isocratically on a 5 μm C18analytical column (50 mm × 4.6 mmi.d.) with buffer–acetonitrile 20:80 (v/v) as mobile phase. The response to metolazone was a linear function of concentration over the range 1.00 to 2000.00 ng mL-1. The lower limit of quantification in plasma was 1.0 ng mL-1. The method was successfully applied in a bioequivalence study of a metolazone formulation after administration as a single oral dose.

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Chadwick, Carrie Ann, and Brian Keevil. "Measurement of cotinine in urine by liquid chromatography tandem mass spectrometry." Annals of Clinical Biochemistry: International Journal of Laboratory Medicine 44, no. 5 (September 1, 2007): 455–62. http://dx.doi.org/10.1258/000456307781645996.

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Background: Cotinine is the major metabolite of nicotine. It is also a specific biomarker for nicotine exposure in cigarette smokers. The measurement of urine cotinine concentration will enable: (1) the assessment of the smoking status of lung transplant patients and (2) tobacco abstinence to be studied in patients during treatment under smoking cessation programmes. Methods: We have developed and validated a method for the measurement of urinary cotinine using reversed phase high-performance liquid chromatography (HPLC) coupled to tandem mass spectrometry (LC-MS/MS). This technique utilizes online ion exchange coupled with an analytical column to eliminate ion suppression effects. The chromatography was performed using a WatersTM 2795 Alliance HT LC system. Results: Cotinine and d3-cotinine had a retention time of 2.5 min and the cycle time from injection to injection was 4 min. The transition identified for cotinine was m/z 177.1>79.6 and for d3-cotinine m/z 180.2>79.6. This method was linear up to 1000 μg/L. Mean recovery of the assay was 112% with a range of 107-117% ( n=9). The limit of quantitation for this assay was 2.5 µg/L and the limit of detection was 0.156 µg/L. The intra- and inter-assay imprecision was <12% and <10% respectively over a concentration range of 22-660 μg/L. Conclusions: We have developed a robust and rapid assay for measuring and analysing urine cotinine by LC-MS/MS, by utilizing a technique, which has reduced ion suppression effects. Ultimately, the method will facilitate the assessment of lung transplant patients' smoking status.

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Pezzatti, Julian, Víctor González-Ruiz, Julien Boccard, Davy Guillarme, and Serge Rudaz. "Evaluation of Different Tandem MS Acquisition Modes to Support Metabolite Annotation in Human Plasma Using Ultra High-Performance Liquid Chromatography High-Resolution Mass Spectrometry for Untargeted Metabolomics." Metabolites 10, no. 11 (November 15, 2020): 464. http://dx.doi.org/10.3390/metabo10110464.

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Ultra-high performance liquid chromatography coupled to high-resolution mass spectrometry (UHPLC-HRMS) is a powerful and essential technique for metabolite annotation in untargeted metabolomic applications. The aim of this study was to evaluate the performance of diverse tandem MS (MS/MS) acquisition modes, i.e., all ion fragmentation (AIF) and data-dependent analysis (DDA), with and without ion mobility spectrometry (IM), to annotate metabolites in human plasma. The influence of the LC separation was also evaluated by comparing the performance of MS/MS acquisition in combination with three complementary chromatographic separation modes: reversed-phase chromatography (RPLC) and hydrophilic interaction chromatography (HILIC) with either an amide (aHILIC) or a zwitterionic (zHILIC) stationary phase. RPLC conditions were first chosen to investigate all the tandem MS modes, and we found out that DDA did not provide a significant additional amount of chemical coverage and that cleaner MS/MS spectra can be obtained by performing AIF acquisitions in combination with IM. Finally, we were able to annotate 338 unique metabolites and demonstrated that zHILIC was a powerful complementary approach to both the RPLC and aHILIC chromatographic modes. Moreover, a better analytical throughput was reached for an almost negligible loss of metabolite coverage when IM-AIF and AIF using ramped instead of fixed collision energies were used.

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Wojtanowski, Krzysztof Kamil, and Tomasz Mroczek. "Detection, Identification and Structural Elucidation of Flavonoids using Liquid Chromatography Coupled to Mass Spectrometry." Current Organic Chemistry 24, no. 1 (April 15, 2020): 104–12. http://dx.doi.org/10.2174/1385272824666200123104815.

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Flavonoids are one of the most common secondary metabolites occurring in plants. Their activity in the Central Nervous System (CNS) including sedative, anxiolytic, anti-convulsive, anti-depressant and neuro-protective actions is well known and documented. The most popular methods for detection, identification and structural elucidation of flavonoids are these based on Nuclear Magnetic Resonance (NMR) and mass spectrometry (MS). NMR allows rapid, high throughput analysis of crude extracts and also gives stereochemical details about identified substances. However, these methods are expensive and less sensitive than MS-based techniques. Combining High Performance Liquid Chromatography (HPLC) with MS detection gives the most powerful tool for analysis of flavonoids occurring in plants. There is a lot of different approaches to use LC/MS based techniques for identification of flavonoids and this short review shows the most important.

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Roy, Shikha M. N., Santos H. M. Yetal, Sangita V. Chavan, Vara D. R. Pradhan, and Santosh S. Joshi. "Determination of Free Levels of Cinitipride in Human Plasma by Liquid Chromatography-Tandem Mass Spectrometry." E-Journal of Chemistry 5, no. 3 (2008): 453–60. http://dx.doi.org/10.1155/2008/242986.

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A rapid, sensitive and specific method to quantify cinitapride in human plasma using risperidone as the internal standard is described. Sample preparation involved simple solid phase extraction procedure. The extract was analyzed by high performance liquid chromatography coupled to electrospray tandem mass spectrometry API-4000 (LC-MS/MS). Chromatography was performed isocratically on Thermo Hypurity C18analytical column, (50 mm x 4.6 mm, 5µm i.d.). The assay of cinitapride was linear calibration curve over the range 20.118 pg mL−1to 2011.797 pg mL−1. Plasma concentrations of cinitapride were determined by LC-MS/MS with a limit of quantification of 20.118 pg mL−1that allowed an appropriate characterization of the pharmacokinetic profile of cinitapride at the therapeutic dose. The method was successfully applied to the bioequivalence study of cinitapride tablet (1.0 mg) administered as a single oral dose.

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Khedr, Alaa, Soad El-Hay, and Ahmed Kammoun. "Multi-Steps Fragmentation-Ion Trap Mass Spectrometry Coupled to Liquid Chromatography Diode Array System for Investigation of Olaparib Related Substances." Molecules 24, no. 5 (February 27, 2019): 843. http://dx.doi.org/10.3390/molecules24050843.

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A high-performance liquid chromatography-diode array-mass spectrometric (LC-DAD-MS) method was developed and validated to investigate the related substances of olaparib (OLA) in bulk form. OLA was exposed to acid–base hydrolysis, boiling, oxidation with hydrogen peroxide, and UV light followed by LC-DAD-MS analysis. OLA and OLA-related substances were simultaneously and quantitatively monitored by DAD at 278 nm and triple quadrupole mass spectrometry (QQQ-MS). The investigated compounds were auto-scanned by an ion trap MS which applied positive and negative modes separately. The fragmentation pathway was confirmed by applying multi-steps fragmentation to identify the resulted cleaved ions and their parent ion. OLA was found to be sensitive to the alkaline hydrolysis and less sensitive to UV light. Two major hydrolytic degradation products, including the protonated molar ions m/z 299 and m/z 367, were identified. Three potential impurities were also characterized. The LC-MS limit of detection (LOD) and limit of quantification (LOQ) were 0.01 and 0.05 ng/µL, respectively. The quantitative results obtained by LC-DAD was comparable with that of LC-QQQ-MS. The proposed method shows good intra-day and inter-day precision with relative standard deviation (RSD) <2%.

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Ciric, Biljana, Dusan Jandric, Vesna Kilibarda, Jasmina Jovic-Stosic, Viktorija Dragojevic-Simic, and Slavica Vucinic. "Simultaneous determination of amoxicillin and clavulanic acid in the human plasma by high performance liquid chromatography: Mass spectrometry (UPLC/MS)." Vojnosanitetski pregled 67, no. 11 (2010): 887–92. http://dx.doi.org/10.2298/vsp1011887c.

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Background/Aim. Quantitative analysis of amoxicillin and clavulanic acid in biological matrices requires sensitive and specific methods which allow determination of therapeutic concentration in ?g/mL range. Analytical methods for determination of their concentrations in body fluids described in literature include high performance liquid chromatography coupled to UV detector (HPLC-UV) and liquid chromatography-mass spectrometry (LC-MS). The aim of this study was to develop sensitive and specific ultra performance liquid chromatography/ mass spectrometry (UPLC/MS) method which could be used for the spectral identification and quantification of the low concentrations of amoxicillin and clavulanic acid in the human plasma. Method. A sensitive and specific UPLC/MS method for amoxicillin and clavulanic acid determination was developed in this study. The samples were taken from the adult healthy volunteers receiving per os one tablet of amoxicillin (875 mg) in combination with clavulanic acid (125 mg). Results. Plasma samples were pretreated by direct deproteinization with perchloric acid. Quantification limit of 0.01 ?g/ml for both amoxicillin and clavulanic acid was achieved. The method was reproducible day by day (RSD < 7 %). Analytical recoveries for amoxicillin ranged from 98.82% to 100.9% (for concentrations of 1, 5 and 20 ?g/mL), and recoveries for clavulanic acid were 99,89% to 100.1% (for concentrations of 1, 2 and 5 ?g/mL). This assay was successfully applied to a pilot pharmacokinetic study in healthy volunteers after a single-oral administration of amoxicillin/ clavulanic combination. The determined plasma concentrations of both amoxicillin and clavulanic acid were in the range of the expected values upon the literature data for HPLC-UV and LC-MS methods. Conclusion. The described method provided a few advantages comparing with LC/MS-MS method. The method is faster using running time of 5 minute, has lower limit of quantification (LOQ ) and it could be used in pharmacokinetic studies of both amoxicillin and clavulanic acid.

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Donno, Dario, Maria Gabriella Mellano, Giovanni Gamba, Isidoro Riondato, and Gabriele Loris Beccaro. "Analytical Strategies for Fingerprinting of Antioxidants, Nutritional Substances, and Bioactive Compounds in Foodstuffs Based on High Performance Liquid Chromatography–Mass Spectrometry: An Overview." Foods 9, no. 12 (November 25, 2020): 1734. http://dx.doi.org/10.3390/foods9121734.

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New technology development and globalisation have led to extreme changes in the agri-food sector in recent years that need an important food supply chain characterisation from plant materials to commercial productions. Many analytical strategies are commonly utilised in the agri-food industry, often using complementary technologies with different purposes. Chromatography on-line coupled to mass spectrometry (MS) is one of the most selective and sensitive analytical methodologies. The purpose of this overview is to present the most recent MS-based techniques applied to food analysis. An entire section is dedicated to the recent applications of high-resolution MS. Covered topics include liquid (LC)– and gas chromatography (GC)–MS analysis of natural bioactive substances, including carbohydrates, flavonoids and related compounds, lipids, phenolic compounds, vitamins, and other different molecules in foodstuffs from the perspectives of food composition, food authenticity and food adulteration. The results represent an important contribution to the utilisation of GC–MS and LC–MS in the field of natural bioactive compound identification and quantification.

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Miroshnichenko, Igor I., and Angelina I. Platova. "Quantification of Amiridine in Human Plasma by High-Performance Liquid Chromatography Coupled with Electrospray Tandem Mass Spectrometry." Chromatography Research International 2013 (September 22, 2013): 1–5. http://dx.doi.org/10.1155/2013/524806.

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The aim of this study was to develop and validate a high-performance liquid chromatographic-tandem mass spectrometric (LC-MS/MS) method for analysis of the amiridine in human plasma. The analyte and internal standard (IS), zolpidem, were extracted from human plasma by solid phase extraction (SPE with SOLA cartridges) and separated on a Zorbax SB-C18 column using methanol and 0.2% formic acid in water as mobile phase. Detection was performed using an electrospray ionization source and mass spectrometric positive multireaction monitoring mode (+MRM) at a voltage capillary of +2000 V. The assay was linear over the concentration range 0.5–200 ng/mL with the lowest limit of quantification (LLOQ) of 0.5 ng/mL. The method also afforded satisfactory results in terms of the sensitivity, specificity, precision (intra- and interday %), accuracy, recovery, and the stability of the analyte under various conditions. The method can be successfully applied to pharmacokinetic studies.

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Won, Joong, Su Son, Sunmin Lee, Digar Singh, Sarah Lee, Jong Lee, and Choong Lee. "Strategy for Screening of Antioxidant Compounds from Two Ulmaceae Species Based on Liquid Chromatography-Mass Spectrometry." Molecules 23, no. 7 (July 23, 2018): 1830. http://dx.doi.org/10.3390/molecules23071830.

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Liquid chromatography-mass spectrometry (LC-MS)-based untargeted metabolomics implies that annotated metabolites can serve as potential markers of the associated bioactivities of plant extracts. Firstly, we selected Aphananthe aspera and Zelkova serrata (Family: Ulmaceae) from 16 Korean plant species based on their distinct principal component analysis (PCA) patterns in LC-MS datasets and antioxidant activity assays. Further, we chose 40% solid-phase extraction (SPE) extracts of the two species displaying the highest antioxidant activities coupled with distinct PCA patterns. Examining the metabolite compositions of the 40% SPE extracts, we observed relatively higher abundances of quercetin, kaempferol, and isorhamnetin O-glucosides for A. aspera, whereas quercetin, isorhamnetin O-glucuronides, and procyanidin dimer were relatively higher in Z. serrata. These metabolites were clearly distinguished in pathway map and displayed strong positive correlations with antioxidant activity. Further, we performed preparative high-performance liquid chromatography (prep-HPLC) analysis coupled with the 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) assay to validate their functional correlations. As a result, quercetin O-sophoroside was determined as the main antioxidant in A. aspera, while isorhamnetin O-glucuronide and procyanidin dimer were the primary antioxidants in Z. serrata. The current study suggests that the LC-MS-based untargeted metabolomics strategy can be used to illuminate subtle metabolic disparities as well as compounds associated with bioactivities.

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Shaheen, Rubi, and S. H. Rizwan. "A Comprehensive Review on The Estimation of Emtricitabine Individually and in Combination With other Drugs." International Journal of PharmTech Research 13, no. 1 (2020): 6–19. http://dx.doi.org/10.20902/ijptr.2019.130102.

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Emtricitabine is a nucleoside reverse transcriptase inhibitor for the prevention of HIV infection. This drug's, clinical and pharmaceutical analysis requires effective analytical procedures and stability studies for quality control and pharmacodynamics and pharmacokinetic studies. A comprehensive literature survey published in various journals related to analytical and pharmaceutical chemistry was conducted and instrumental analytical methods were developed and used in bulk drugs and pharmaceutical dosage form as single and combined with other drugs. This review will critically examine UV spectroscopy analytical methods (simultaneous equation method, derivative spectrophotometric method, absorption ratio and Qbased method), High-performance liquid chromatography (HPLC), High-performance thinlayer chromatography (HPTLC), Liquid chromatography coupled with tandem mass spectrometry (LC-MS).

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Pantano, Licia, Ladislao La Scala, Francesco Olibrio, Francesco Giuseppe Galluzzo, Carmelo Bongiorno, Maria Drussilla Buscemi, Andrea Macaluso, and Antonio Vella. "QuEChERS LC–MS/MS Screening Method for Mycotoxin Detection in Cereal Products and Spices." International Journal of Environmental Research and Public Health 18, no. 7 (April 4, 2021): 3774. http://dx.doi.org/10.3390/ijerph18073774.

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We developed and validated a screening method for mycotoxin analysis in cereal products and spices. Ultra-high-performance liquid chromatography coupled with tandem mass spectrometry (UHPLC–MS/MS) was used for the analysis. Dispersive solid-phase extractions (d-SPEs) were used for the extraction of samples. Ochratoxin A (OTA), zearalenone (ZEA), aflatoxins (AFLA; AFB1, AFB2, AFG1, AFG2), deoxynivalenol (DON), fumonisin (FUMO; FB1, FB2, FB3), T2, and HT2 were validated in maize. AFLA and DON were validated in black pepper. The method satisfies the requirements of Commission Regulation (EC) no. 401/2006 and (EC) no. 1881/2006. The screening target concentration (STC) was under maximum permitted levels (MLs) for all mycotoxins validated. The method’s performance was assessed by two different proficiencies and tested with 100 real samples.

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Shen, Shihao, Min Chen, Tiannan Wang, Ting Fei, Dianhai Yang, Miaoling Cao, and Da Wu. "Determination of Methomyl Residue in Tobacco Samples by Heart-Cutting Two-Dimensional Liquid Chromatography with Tandem Mass Spectrometry." International Journal of Analytical Chemistry 2020 (October 13, 2020): 1–6. http://dx.doi.org/10.1155/2020/8813142.

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A novel heart-cutting two-dimensional liquid chromatography coupled with tandem mass spectrometry (2D-LC-MS/MS) was developed for the qualitative and quantitative analysis of methomyl residue in tobacco. Compared to traditional methodologies, fairly high sensitivity and stability were achieved, and the sample procedure was simplified in the two-dimensional liquid chromatography (2D-LC) method. Although methomyl had poor retention performance in most of the reversed-phase liquid chromatography (RPLC) columns, an effective RP/RP strategy was successfully facilitated. An XB-Phenyl column was employed in the first dimension to effectively remove thousands of interference compounds in the matrix. In the second dimension, an ADME column was applied for further separation. After optimization of the separation conditions, a six-way valve was utilized for direct transformation of the target fraction from the 1st column to the 2nd column. A dynamic range of 2.5 ng/mL to 500 ng/mL was achieved with correlation coefficient (r2) greater than 0.9995. The limit of detection and limit of quantification were determined to be 0.69 and 2.30 ng/mL, respectively. The 2D-LC method shows high sensitivity, good reproducibility, and recovery for methomyl in tobacco samples. Therefore, the new method was quite suitable for routine analysis.

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Wang, Jian, Wendy Cheung, and Willis Chow. "Ultra-High Performance Liquid Chromatography/Electrospray Ionization-Tandem Mass Spectrometry Determination of 151 Pesticides in Soybeans and Pulses." Journal of AOAC INTERNATIONAL 96, no. 5 (September 1, 2013): 1114–33. http://dx.doi.org/10.5740/jaoacint.12-465.

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Abstract This paper presents the application of ultra-high performance LC (UHPLC) and MS for the determination of 151 pesticides in soybeans and pulses. A core-shell particle (2.6 μm particle size) column and a fully porous sub-2 μm (1.7 μm particle size) column showed comparable performance in chromatographic resolution and separation, increasing selectivity, and reducing analysis time. UHPLC was coupled with either a triple quadrupole mass analyzer (MS/MS) or a quadrupole Orbitrap (namely Orbital trap) mass spectrometer (Q-Orbitrap MS), which possesses fast data acquisition capability. Both configurations yielded analytical run times of ≤14 min. Soybean and pulse samples were analyzed and quantitated for pesticide residues using the QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) procedure, UHPLC/electrospray ionization (ESI)-MS/MS, and matrix-matched standard calibration curves (in an analytical range of 5–500 μg/kg) with isotopically-labeled standards or a chemical analog as internal standards. The method performance parameters that included overall recovery, intermediate precision, and measurement uncertainty were evaluated according to a nested design experiment. Approximately 89% of the pesticides studied had recoveries between 81 and 110%; 95%, had intermediate precision ≤20%; and 93% showed measurement uncertainty ≤40%. From a pilot study of 100 samples, eight tested positive by UHPLC/ESI-MS/MS for carbendazim, methomyl, or imidacloprid. These pesticides were further confirmed using UHPLC/ESI-Q-Orbitrap MS based on accurate mass measurement with mass error ≤5 ppm.

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Pascale, Michelangelo. "Detection methods for mycotoxins in cereal grains and cereal products." Zbornik Matice srpske za prirodne nauke, no. 117 (2009): 15–25. http://dx.doi.org/10.2298/zmspn0917015p.

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Analytical methods for mycotoxins in cereals and cereal-based products require three major steps, including extraction, clean-up (to eliminate interferences from the extract and concentrate the analyte), and detection/determination of the toxin (by using suitable analytical instruments/technologies). Clean-up is essential for the analysis of mycotoxins at trace levels, and involves the use of solid phase extraction and multifunctional (e.g. MycoSep?) or immunoaffinity columns. Different chromatographic methods are commonly used for quantitative determination of mycotoxins, including gas-chromatography (GC) coupled with electron capture, flame ionization or mass spectrometry (MS) detectors (mainly for type-A trichothecenes), and high-performance liquid chromatography (HPLC) coupled with ultraviolet, diode array, fluorescence or MS detectors. The choice of method depends on the matrix and the mycotoxin to be analyzed. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) is spreading rapidly as a promising technique for simultaneous screening, identification and quantitative determination of a large number of mycotoxins. In addition, commercial immunometric assays, such as enzyme-linked immunosorbent assays (ELISA), are frequently used for screening purposes as well. Recently, a variety of emerging methods have been proposed for the analysis of mycotoxins in cereals based on novel technologies, including immunochromatography (i.e. lateral flow devices), fluorescence polarization immunoassays (FPIA), infrared spectroscopy (FT-NIR), molecularly imprinted polymers (MIPs) and optical biosensors.

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Cazzaniga, Noemi, Zsuzsanna Varga, Edith Nicol, and Stéphane Bouchonnet. "UV-visible photodegradation of naproxen in water – Structural elucidation of photoproducts and potential toxicity." European Journal of Mass Spectrometry 26, no. 6 (November 11, 2020): 400–408. http://dx.doi.org/10.1177/1469066720973412.

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The UV-visible photodegradation of Naproxen (6-methoxy-α-methyl-2-naphthaleneacetic acid, CAS: 22204-53-1), one of the most used and detected non-steroidal anti-inflammatory drugs (NSAIDs) in the world, and its ecotoxicological consequences were investigated in an aqueous medium. The photo-transformation products were analyzed and the structures of photoproducts were elucidated using gas chromatography coupled with tandem mass spectrometry (GC-MS/MS) and high-performance liquid chromatography coupled with ultrahigh-resolution Fourier transform ion cyclotron resonance mass spectrometry (LC-FTICR-MS). Seven photoproducts were detected and characterized, photo-transformation mechanisms have been postulated to rationalize their formation under irradiation. In silico Q.S.A.R. (Quantitative Structure-Activity Relationship) toxicity predictions were performed with the Toxicity Estimation Software Tool (T.E.S.T.) and in vitro assays were carried out on Vibrio fischeri bacteria. Some of the obtained photoproducts exhibit higher potential toxicity than Naproxen itself but the whole toxicity of the irradiated solution is not of major concern.

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Wongchang, Thamrong, Markus Winterberg, Joel Tarning, Natthida Sriboonvorakul, Sant Muangnoicharoen, and Daniel Blessborn. "Determination of ceftriaxone in human plasma using liquid chromatography–tandem mass spectrometry." Wellcome Open Research 4 (March 8, 2019): 47. http://dx.doi.org/10.12688/wellcomeopenres.15141.1.

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Ceftriaxone is a cephalosporin antibiotic drug used as first-line treatment for several bacterial diseases. Ceftriaxone belongs to the third generation of antibiotics and is available as an intramuscular or intravenous injection. Previously published pharmacokinetic studies have mainly used high-performance liquid chromatography coupled with ultraviolet detection (HPLC-UV) for the quantification of ceftriaxone. This study aimed to develop and validate a bioanalytical method for the quantification of ceftriaxone in human plasma using liquid chromatography followed by tandem mass spectrometry (LC-MS/MS). Sample preparation was performed by protein precipitation in combination with phospholipid-removal techniques for cleaning up matrix interferences. The chromatographic separation was performed on an Agilent Zorbax Eclipse Plus C18 column with 10 mM ammonium formate containing 2% formic acid: acetonitrile as mobile phase at a flow rate of 0.4 ml/min. Both the analyte and cefotaxime (internal standard) were quantified using the positive electrospray ionization (ESI) mode and selected reaction monitoring (SRM) for the precursor-product ion transitions m/z 555.0→396.1 for ceftriaxone and 456.0→324.0 for cefotaxime. The method was validated over the concentration range of 1.01-200 μg/ml. Calibration response showed good linearity (correlation coefficient > 0.99) and no significant matrix effects were observed. The intra-assay and inter-assay precision were less than 5% and 10%, respectively, and therefore well within standard regulatory acceptance criterion of ±15%.

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Xizheng, Yan, Liza Valentín-Blasini, Clifford Watson, and Roberto Bravo Cardenas. "Determination of Humectants in Tobacco Filler by High Performance Chromatography/Single Quadrupole Mass Spectrometry." Beiträge zur Tabakforschung International/Contributions to Tobacco Research 28, no. 4 (December 1, 2018): 170–78. http://dx.doi.org/10.2478/cttr-2018-0016.

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SummaryGlycerol, and 1,2-propylene glycol are the humectants most commonly used by the tobacco industry. They are found in a variety of tobacco products and are often present at high levels (~2–5 % w/w). While humectants are generally considered safe, they may serve as precursors in the formation of harmful carbonyl compounds. A selective, precise, and sensitive method for the quantification of several humectants in cigarette filler was developed. The method’s sample clean-up is a two-step process consisting of a mechanical extraction, followed by solid phase extraction. Individual humectants are separated, identified, and measured using liquid chromatography coupled to a single quadrupole mass spectrometer as the detector (LC/MS). Detection limits were 0.105, 0.575, and 0.039 mg/cigarette for glycerol, 1,2-propylene glycol and triethylene glycol, respectively. The quantification range for these analytes was 0.4–75.0 mg/cigarette. Twenty-seven brands of domestic commercial cigarettes were evaluated to assess typical levels of humectants in the tobacco filler.

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Tuzimski, Tomasz, and Anna Petruczynik. "Review of Chromatographic Methods Coupled with Modern Detection Techniques Applied in the Therapeutic Drugs Monitoring (TDM)." Molecules 25, no. 17 (September 3, 2020): 4026. http://dx.doi.org/10.3390/molecules25174026.

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Therapeutic drug monitoring (TDM) is a tool used to integrate pharmacokinetic and pharmacodynamics knowledge to optimize and personalize various drug therapies. The optimization of drug dosing may improve treatment outcomes, reduce toxicity, and reduce the risk of developing drug resistance. To adequately implement TDM, accurate and precise analytical procedures are required. In clinical practice, blood is the most commonly used matrix for TDM; however, less invasive samples, such as dried blood spots or non-invasive saliva samples, are increasingly being used. The choice of sample preparation method, type of column packing, mobile phase composition, and detection method is important to ensure accurate drug measurement and to avoid interference from matrix effects and drug metabolites. Most of the reported procedures used liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) techniques due to its high selectivity and sensitivity. High-performance chromatography with ultraviolet detection (HPLC-UV) methods are also used when a simpler and more cost-effective methodology is desired for clinical monitoring. The application of high-performance chromatography with fluorescence detection (HPLC-FLD) with and without derivatization processes and high-performance chromatography with electrochemical detection (HPLC-ED) techniques for the analysis of various drugs in biological samples for TDM have been described less often. Before chromatographic analysis, samples were pretreated by various procedures—most often by protein precipitation, liquid–liquid extraction, and solid-phase extraction, rarely by microextraction by packed sorbent, dispersive liquid–liquid microextraction. The aim of this article is to review the recent literature (2010–2020) regarding the use of liquid chromatography with various detection techniques for TDM.

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Zekič, Jure, Irena Vovk, and Vesna Glavnik. "Extraction and Analyses of Flavonoids and Phenolic Acids from Canadian Goldenrod and Giant Goldenrod." Forests 12, no. 1 (December 30, 2020): 40. http://dx.doi.org/10.3390/f12010040.

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Invasive alien plant species Canadian goldenrod (Solidago canadensis L.) and giant goldenrod (Solidago gigantea Aiton) were investigated as a source of phytochemicals and yellow dyes. Flavonoids and phenolic acids were extracted from the inflorescence of Canadian goldenrod with thirteen extraction solvents ethanol, methanol, acetone, water, and mixtures of organic solvents (70%, 80%, and 90%) with water. High performance thin-layer chromatography (HPTLC) coupled to densitometry and high-performance liquid chromatography with photo-diode array detector (HPLC-PDA) were used for analyses of the obtained sample test solutions (STSs), which showed the best and comparable extraction efficiencies for 70% acetone(aq), 70% methanol(aq), and 70% ethanol(aq). HPTLC combined with image analyses in fluorescent mode resulted in different chromatographic fingerprints for Canadian goldenrod and giant goldenrod STSs (70% acetone(aq)) after development, after post-chromatographic derivatization with NP reagent and after use of PEG reagent. The developed HPLC methods enabled analyses of phenolic acids and flavonoids (aglycones and glycosylated) in STSs and hydrolyzed STSs form inflorescence of Canadian and giant goldenrod. Different contents of chlorogenic acid, rutin, hyperoside, isoquercetin, and quercetin were observed in STSs of both goldenrod species. The analyses of hydrolyzed STSs confirmed that glycosylated flavonoids in Canadian and giant goldenrod inflorescence are mainly glycosides of quercetin, kaempferol, and isorhamnetin. Additional analyses using HPTLC and HPLC coupled to tandem mass spectrometry (MS/MS; HPTLC-MS/MS and LC-MS/MS) enabled tentative identification of phenolic acids and flavonoids (10 with HPTLC-MS/MS and 15 with LC-MS/MS), from which several were identified in Canadian (4 with HPTLC-MS/MS and 8 with LC-MS/MS) and in giant (7 with HPTLC-MS/MS and 9 with LC-MS/MS) goldenrod for the first time.

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Liang, MingJin, WeiDong Zhang, Chuan Zhang, YunHeng Shen, XiaoLin Wang, and Xiangwei Wang. "Simultaneous Determination of Vitexin Rhamnoside and Vitexin Glucoside in Rats by Liquid Chromatography Coupled with Mass Spectrometry." Natural Product Communications 3, no. 5 (May 2008): 1934578X0800300. http://dx.doi.org/10.1177/1934578x0800300504.

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The purpose of the present study was to evaluate the pharmacokinetic interaction of vitexin rhamnoside (vitexin 2″-α-L-rhamnopyranosyl) and vitexin glucoside (vitexin 2″-β-D-glucopyranosyl) in rats by using a high performance liquid chromatography coupled with tandem mass spectrometry quantitative detection method (LC-MS/MS). The method was validated at the concentration range of 5 - 5000 ng/mL for both vitexin rhamnoside and vitexin glucoside with the regression equations Y = 0.00181X - 0.000955 ( r > 0.998) and Y = 0.000788X - 0.000373 ( r > 0.997), respectively. The methodological studies (including linearity, intra-assay / inter-assay accuracy and precision) of these two components were investigated. The pharmacokinetic parameters of these two components were compared, which demonstrated their pharmacokinetic variance, especially when they were administrated simultaneously.

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Faccin, Henrique, Roberta Fabricio Loose, Carine Viana, Osmar A. Lameira, and Leandro Machado de Carvalho. "Determination of phenolic compounds in extracts of Amazonian medicinal plants by liquid chromatography-electrospray tandem mass spectrometry." Analytical Methods 9, no. 7 (2017): 1141–51. http://dx.doi.org/10.1039/c6ay02937j.

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A method for the separation, identification and quantification of 24 phenolic compounds using ultra-high performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS) was developed and validated.

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Nakajima, Jun-ichiro, Ippei Tanaka, Shujiro Seo, Mami Yamazaki, and Kazuki Saito. "LC/PDA/ESI-MS Profiling and Radical Scavenging Activity of Anthocyanins in Various Berries." Journal of Biomedicine and Biotechnology 2004, no. 5 (2004): 241–47. http://dx.doi.org/10.1155/s1110724304404045.

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Anthocyanin extracts of two blueberries,Vaccinium myrtillus(bilberry) andVaccinium ashei(rabbiteye blueberry), and of three other berries,Ribes nigrum(black currant),Aronia melanocarpa(chokeberry), andSambucus nigra(elderberry), were analyzed by high-performance liquid chromatography coupled with photodiode array detection and electrospray ionization - mass spectrometry (LC/PDA/ESI-MS). Both bilberry and rabbiteye blueberry contained 15 identical anthocyanins with different distribution patterns. Black currant, chokeberry, and elderberry contained 6, 4, and 4 kinds of anthocyanins, respectively. The radical scavenging activities of these berry extracts were analyzed by using 2,2-diphenyl-1-picrylhydrazyl (DPPH). All these extracts showed potent antiradical activities.

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Huang, Aihua, Yuguang Chi, Jiawei Liu, Mincun Wang, Jialiang Qin, Lijuan Ou, Weiwen Chen, Zhongxiang Zhao, Ruoting Zhan, and Hui Xu. "Profiling and Pharmacokinetic Studies of Alkaloids in Rats After Oral Administration of Zanthoxylum nitidum Decoction by UPLC-Q-TOF-MS/MS and HPLC-MS/MS." Molecules 24, no. 3 (February 7, 2019): 585. http://dx.doi.org/10.3390/molecules24030585.

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Zanthoxylum nitidum (Roxb.) DC (Rutaceae), called as “liangmianzhen” in China, is well known for its anti-inflammation and analgesic effect. Alkaloids are its main active constituents. However, little has been known about the absorption of main alkaloids in vivo. In this study, an ultra-performance liquid chromatography coupled with quadrupole-time-of-flight mass spectrometry was employed for identification of absorbed alkaloids in rats after oral administration of Z. nitidum decoction. By analyzing the fragmentation patterns, a total of nineteen alkaloids were exactly or tentatively identified in rat plasma after treatment, of which magnoflorine, α-allocryptopine, and skimmianine are dominant. Moreover, a high performance liquid chromatography coupled mass spectrometry method was developed for simultaneous quantification of magnoflorine, α-allocryptopine, and skimmianine, and successfully applied to pharmacokinetic study in rats after oral administration of Z. nitidum decoction. The research would contribute to comprehensive understanding of the material basis and function mechanism of Z. nitidum decoction.

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Jakubska-Busse, Anna, Izabela Jasicka-Misiak, Anna Poliwoda, Emilia Święczkowska, and Paweł Kafarski. "The chemical composition of the floral extract of Epipogium aphyllum sw. (Orchidaceae): A clue for their pollination biology." Archives of Biological Sciences 66, no. 3 (2014): 989–98. http://dx.doi.org/10.2298/abs1403989b.

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Epipogium aphyllum is a rare European obligate mycoheterotrophic orchid lacking chlorophyll. It has not been studied previously with respect to pollination biology. We studied the association between the composition of floral scent emission and its pollination systems. Field observation indicates that the main pollinators of Epipogium aphyllum are representatives of the genus Bombus (Hymenoptera), B. lucorum, B. hortorum, B. terrestris, B. pascuorum and B. proteus, and the genus Apis (Hymenoptera) namely A. mellifera. The main potential vector (observed to accidentally carry pollen), is most likely Episyrphus balteatus (Diptera, Syrphidae). The chemical composition of the floral extracts of 4 populations of Epipogium aphyllum Sw. growing naturally in Poland and the Czech Republic was examined by gas chromatography coupled with mass spectrometry (GC-MS) and high-performance liquid chromatography coupled with diode-array detection and electrospray ionization mass spectrometry (LC-ESI-MS) techniques. According to GC-MS analysis, 9-tricosene, nonadecane, 1-nonadecene and nonacosane predominated in the floral extracts. The studied samples were also characterized by relatively high amounts of benzenoids, e.g. methyl cinnamate, which is known as an attractant to the males of various orchid bees. LC-ESI-MS revealed the presence of flavor compounds such as vanillin (4-hydroxy-3-methoxybenzaldehyde) and its derivative acetovanillone, together with higher amounts of aliphatic and phenolic acids. Additionally, we detected the presence of indole and morphine derivatives.

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Giusepponi, Paoletti, Barola, Moretti, Saluti, Ianni, Sardella, and Galarini. "Transfer of a Multiclass Method for over 60 Antibiotics in Food from High Resolution to Low Resolution Mass Spectrometry." Molecules 24, no. 16 (August 13, 2019): 2935. http://dx.doi.org/10.3390/molecules24162935.

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A multiclass method has been developed to screen and confirm a wide range of anti-microbial residues in muscle and milk, and validated using liquid-chromatography coupled to (low-resolution, LR) tandem mass spectrometry (LC-QqQ). Over sixty antibiotics, belonging to ten distinct families, were included in the method scope. The development process was rapidly concluded as a result of two previously implemented methods. This consisted of identical sample treatments, followed by liquid chromatography, and coupled with high-resolution (HR) mass spectrometry (LC-Q-Orbitrap). The validation study was performed in the range between 10–1500 μg·kg−1 for muscles and 2–333 μg·kg−1 for milk. The main performance characteristics were estimated and, then, compared to those previously obtained with HR technique. The validity of the method transfer was ascertained also through inter-laboratory studies.

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Lin, Chao-Zhan, Run-Jing Zhang, Yu-Feng Yao, Xiao-Dan Huang, Rong-Bo Zheng, Bo-Jian Wu, and Chen-Chen Zhu. "Qualitative and Quantitative Analysis of the Major Constituents in WLJ Herbal Tea Using Multiple Chromatographic Techniques." Molecules 23, no. 10 (October 12, 2018): 2623. http://dx.doi.org/10.3390/molecules23102623.

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Quality control of Chinese herbal tea remains a challenge due to our poor knowledge of their complex chemical profile. This study aims to investigate the chemical composition of one of the best-selling and famous brand of beverage in China, Wanglaoji Herbal Tea (WLJHT), via a full component quantitative analysis. In this paper, a total of thirty-two representative constituents were identified or tentatively characterized using ultra-high performance liquid chromatography coupled with quadrupole tandem time-of-flight mass spectrometry (UPLC-Q-TOF-MS). Moreover, the quantitative analyses of fourteen constituents were performed by high performance liquid chromatography with a triple quadruple tandem mass spectrometry (HPLC-MS/MS) method and saccharide compositions of WLJHT were also quantitatively determined by high performance liquid chromatography (HPLC) with evaporative light scattering detector (ELSD) on a Hilic column, separately. Using multiple chromatographic techniques presented a good precision, sensitivity, repeatability and stability, and was successfully applied to analyze 16 batches of WLJHT samples. Therefore, it would be a reliable and useful approach for the quality control of WLJHT.

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Zhang, Yuchi, Jingying Xu, Chunming Liu, and Sainan Li. "Screening of neuraminidase inhibitors from the leaves of Syringa velutina Kom. via compound fractionation and in vitro activity evaluation." Analytical Methods 9, no. 3 (2017): 500–510. http://dx.doi.org/10.1039/c6ay02922a.

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A novel hyphenated technique comprised of circulating ultrasound-assisted extraction (CUAE) coupled with an online solvent concentration tank (SCT), centrifugal partition chromatography (CPC), ultra-high performance liquid chromatography (UPLC), and mass spectrometry (MS) was established.

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Metzger, S., and Bernd O. Kolbesen. "Application of HPLC for the Analysis of Organic Additives in Cleaning Chemicals and Cleaning Mixtures." Solid State Phenomena 103-104 (April 2005): 221–26. http://dx.doi.org/10.4028/www.scientific.net/ssp.103-104.221.

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The suitability of high performance liquid chromatography (HPLC) for the direct determination of the concentration of complexing agents for single chemistry cleaning is demonstrated. HPLC, coupled to a mass spectrometric detector (HPLC-MS) and two-dimensional mass spectrometry (MS/MS) have been applied for the investigation of the reactions involved in the decomposition of the complexing agents. The techniques described are useful for determining the stability of organic additives in wet chemical cleaning baths.

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Yuldasheva, Shokhida Saitovna, Nodira Abdulxamitovna Yunuskhodjaeva, Shakhriddin Shavkat Ugli, and Alimjon Davlatboevich Matchanov. "Study Of The Chemical Composition Of The Liquid Extract "Extradent"." American Journal of Medical Sciences and Pharmaceutical Research 03, no. 03 (March 6, 2021): 1–11. http://dx.doi.org/10.37547/tajmspr/volume03issue03-01.

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The quantitative content of flavonoids of the aerial part of the plant was determined by high performance liquid chromatography (HPLC). Using the inductively coupled plasma mass spectrometry (ICP-MS) method, the quantitative content of vital macro-and microelements in the various vegetative organs of the plant was determined.

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Sivasubramaniam, Varatharajan, Florian Brodkorb, Stephanie Hanning, Hans Loebl, Volker Elsbergen, Herbert Boerner, Ullrich Scherf, and Martin Kreyenschmidt. "Investigation of FIrpic in PhOLEDs via LC/MS technique." Open Chemistry 7, no. 4 (December 1, 2009): 836–45. http://dx.doi.org/10.2478/s11532-009-0084-1.

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AbstractThe commercial breakthrough of phosphorescent organic white light sources is presently hampered due to the unavailability of a stable blue phosphorescent emitter material. Moreover, only few analytical investigations have been made regarding the chemical degradation of the phosphorescent emitter materials during the processing or the operation of the devices. Organic light emitting devices (OLEDs) containing phosphorescent metal complexes with iridium as central ion were investigated. Special attention was paid to the chemical degradation of the material. The devices were analyzed by means of high performance liquid chromatography coupled with mass spectrometry (HPLC/MS). Electron spray ionization (ESI) was employed as ionization source. Isomerization phenomena of the blue-green emitting heteroleptic iridium complex FIrpic could be observed after the device manufacture and after operation. These findings could give hints on the mechanisms that influence the lifetime of PhOLEDs based on FIrpic or similar blue emitters.

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Rigato, H. Modesto, G. Duarte Mendes, N. Carter do Carmo Borges, and R. A. Moreno. "Meloxicam determination in human plasma by high-performance liquid chromatography coupled with tandem mass spectrometry (LC-MS-MS) in Brazilian bioequivalence studies." Int. Journal of Clinical Pharmacology and Therapeutics 44, no. 10 (October 1, 2006): 489–98. http://dx.doi.org/10.5414/cpp44489.

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Schröder, H. Fr. "Polar Organic Pollutants on Their Way from Waste Water to Drinking Water." Water Science and Technology 25, no. 11 (June 1, 1992): 241–48. http://dx.doi.org/10.2166/wst.1992.0298.

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The examination of pollutants in waste-, surface- and drinking water by sum parameters like COD, BOD or TOC gives no information about their toxicity or behaviour in the drinking water treatment process. As many pollutants leaving sewage treatment plants are polar and/or thermolabile, gas Chromatographic (GC) separation coupled on-line with a mass spectrometer (MS) is not applicable to this problem. Newly established analytical methods like high performance liquid chromatography (HPLC) in on-line combination with mass- (MS) or tandem mass spectrometers (MS/MS) using soft ionization techniques like thermospray (TSP) would help to solve these problems. The comparison of GC- and LC/MS-spectra demonstrates increasing polarity beginning at the waste water treatment and ending at the drinking water treatment. It was possible to identify and quantify selected compounds, and elimination efficiency could be reviewed by comparing overview spectra. The knowledge about the existence of these compounds in waste-, surface- and drinking water requires strategies for elimination, avoidance or degradation.

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Wang, Jingchen, Jianmei Tao, Shuailong Jia, Meiqin Wang, Hongliang Jiang, and Zhifeng Du. "The Protein-Binding Behavior of Platinum Anticancer Drugs in Blood Revealed by Mass Spectrometry." Pharmaceuticals 14, no. 2 (January 29, 2021): 104. http://dx.doi.org/10.3390/ph14020104.

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Cisplatin and its analogues are widely used as chemotherapeutic agents in clinical practice. After being intravenously administrated, a substantial amount of platinum will bind with proteins in the blood. This binding is vital for the transport, distribution, and metabolism of drugs; however, toxicity can also occur from the irreversible binding between biologically active proteins and platinum drugs. Therefore, it is very important to study the protein-binding behavior of platinum drugs in blood. This review summarizes mass spectrometry-based strategies to identify and quantitate the proteins binding with platinum anticancer drugs in blood, such as offline high-performance liquid chromatography/inductively coupled plasma mass spectrometry (HPLC–ICP-MS) combined with electrospray ionization mass spectrometry (ESI-MS/MS) and multidimensional LC–ESI-MS/MS. The identification of in vivo targets in blood cannot be accomplished without first studying the protein-binding behavior of platinum drugs in vitro; therefore, relevant studies are also summarized. This knowledge will further our understanding of the pharmacokinetics and toxicity of platinum anticancer drugs, and it will be beneficial for the rational design of metal-based anticancer drugs.

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Pigliasco, Federica, Sebastiano Barco, Sara Dubois, Francesca Marchese, Pasquale Striano, Tommaso Lomonaco, Francesca Mattioli, Gino Tripodi, and Giuliana Cangemi. "Cannabidiol Determination on Peripheral Capillary Blood Using a Microsampling Method and Ultra-High-Performance Liquid Chromatography Tandem Mass Spectrometry with On-Line Sample Preparation." Molecules 25, no. 16 (August 8, 2020): 3608. http://dx.doi.org/10.3390/molecules25163608.

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The aim of this work is to evaluate volumetric absorptive microsampling (VAMS) from capillary blood as an alternative strategy for therapeutic drug monitoring (TDM) in patients treated with the newly available GW-purified form of cannabidiol (Epidiolex®). A fast ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) coupled to an online sample preparation system analysis was carried out on a Thermo Scientific Ultimate 3000 LC system coupled to a TSQ Quantiva triple quadrupole for the quantification of cannabidiol (CBD) and, in addition, delta-9-tetrahydrocannabinol (Δ9-THC). After validation using European Medicine Agency (EMA) guidelines the method was applied to samples obtained by finger prick of five pediatric patients treated with Epidiolex® and the results were compared to those obtained from venous blood and plasma. The method is linear in the range of 1–800 µg/L for both CBD and THC with intra- and inter-day precisions ranging from 5% to 14% and accuracies from −13% to +14% starting from 30 µL of sample. Stability in VAMS is ensured for up to 4 weeks at 25 °C thus allowing simple delivery. There was no difference (p = 0.69) between concentrations of CBD measured from VAMS sampled from capillary or venous blood (range: 52.19–330.14 or 72.15–383.45 µg/L) and those obtained from plasma (range: 64.3–374.09 µg/L) The VAMS-LC-MS/MS method represents a valid alternative strategy for therapeutic drug monitoring of patients treated with Epidiolex®.

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Markoglou, Anastasios N., Eleftheria D. Bempelou, Konstantinos S. Liapis, and Basil N. Ziogas. "Determination of Benzoylurea Insecticide Residues in Tomatoes by High-Performance Liquid Chromatography with Ultraviolet-Diode Array and Atmospheric Pressure Chemical Ionization-Mass Spectrometry Detection." Journal of AOAC INTERNATIONAL 90, no. 5 (September 1, 2007): 1395–401. http://dx.doi.org/10.1093/jaoac/90.5.1395.

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Abstract A simple and sensitive method using high-performance liquid chromatography/mass spectrometry (LC/MS) was developed and validated for simultaneous determination of 5 benzoylurea insecticidesdiflubenzuron, triflumuron, teflubenzuron, lufenuron, and flufenoxuronin tomatoes. Residues were successfully separated on a C18 column by methanolwater isocratic elution. Detection was carried out by an ultraviolet diode array detector (UV-DAD) coupled with a quadrupole mass spectrometer, using atmospheric pressure chemical ionization (APCI) in negative-ion mode. The main ions were the deprotonated molecules [MH]<sup/> for triflumuron, and the anions formed by elimination of hydrofluoric acid [MHHF]<sup/> for diflubenzuron and flufenoxuron, and [M2HHF] for lufenuron and teflubenzuron. The calibration plots were linear for both detectors over the range 0.05 to 10 g/mL, and the method presented good quality parameters. The limits of detection for standard solutions were 0.0080.01 mg/L (equivalent to 0.080.1 ng injected) for both detectors, and the limits of quantification (LOQs) were approximately 10 times lower than national maximum residue levels (MRLs). Depending on the compound and the detector, the LOQ values ranged from 0.2 to 0.4 ng injected. The optimum LC-UV-DAD/APCI-MS conditions were applied to the analysis of benzoylureas in tomatoes. The obtained recoveries from fortified tomato samples (50 g), extracted with ethyl acetate and purified by solid-phase extraction on silica sorbent, were 88100 and 92.9105 for the UV-DAD and MS detectors, respectively, with precision values (relative standard deviations) of 2.911 and 3.714, respectively. The method was applied to 12 tomato samples from local markets, and diflubenzuron and lufenuron were detected in only one sample at concentrations lower than the MRLs. The results indicate that the developed LC/MS method is accurate, precise, and sensitive for quantitative and qualitative analysis at low levels of benzoylureas required by legislation.

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Waś, J., M. Niedolistek, A. Wróbel, S. Malina, A. Prejbisz, A. Januszewicz, D. Rabczenko, and A. Lutyńska. "Comparison of mass spectrometry coupled to liquid chromatography (LC-MS/MS) & high performance liquid chromatography with coulometric detection (HPLC-CD) for determination of catecholamine – producing tumors." Clinica Chimica Acta 493 (June 2019): S67. http://dx.doi.org/10.1016/j.cca.2019.03.149.

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Zvereva, I. O., N. B. Savelieva, P. V. Postnikov, Yu A. Efimova, and M. A. Dikunets. "APPROACHES TO CHORIONIC GONADOTROPIN QUANTITATIVE DETERMINATION IN ANTI-DOPING CONTROL." Fine Chemical Technologies 12, no. 1 (February 28, 2017): 64–75. http://dx.doi.org/10.32362/2410-6593-2017-12-1-64-75.

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The article presents the results of the first stage of development of a new quantitative method for human chorionic gonadotropin (hCG) determination by means of ultra-high performance liquid chromatography coupled to tandem mass spectrometry (UPLC-MS/MS) to uncover doping abuse by athletes. The identified tryptic peptides correspond to the most abundant hCG isoforms: the α- and β-subunits, the nicked and β-core fragment of the hormone. Identification and sequencing of specific fragments were performed with the use of nanoLC-MS/MS. A high resolution / high accuracy hybrid mass-spectrometer was applied. Optimization of mass-spectrometric determination of selected specific peptides was accomplished by UPLC-MS/MS. Quantitative evaluation of hCG using specific fragments determination by UPLC-MS/MS allows to detect corresponding hCG isoforms. This significantly increases the method specificity and decreases the probability of false-positive results.

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Maldini, Mariateresa, Gilda D’Urso, Giordana Pagliuca, Giacomo Luigi Petretto, Marzia Foddai, Francesca Romana Gallo, Giuseppina Multari, Donatella Caruso, Paola Montoro, and Giorgio Pintore. "HPTLC-PCA Complementary to HRMS-PCA in the Case Study of Arbutus unedo Antioxidant Phenolic Profiling." Foods 8, no. 8 (July 27, 2019): 294. http://dx.doi.org/10.3390/foods8080294.

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A comparison between High-Performance Thin-Layer Chromatography (HPTLC) analysis and Liquid Chromatography High Resolution Mass Spectrometry (LC–HRMS), coupled with Principal Component Analysis (PCA) was carried out by performing a combined metabolomics study to discriminate Arbutus unedo (A. unedo) plants. For a rapid digital record of A. unedo extracts (leaves, yellow fruit, and red fruit collected in La Maddalena and Sassari, Sardinia), HPTLC was used. Data were then analysed by PCA with the results of the ability of this technique to discriminate samples. Similarly, extracts were acquired by non-targeted LC–HRMS followed by unsupervised PCA, and then by LC–HRMS (MS) to identify secondary metabolites involved in the differentiation of the samples. As a result, we demonstrated that HPTLC may be applied as a simple and reliable untargeted approach to rapidly discriminate extracts based on tissues and/or geographical origins, while LC–HRMS could be used to identify which metabolites are able to discriminate samples.

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Qi, Chen, Guo Tianyang, Yao Jian, Liao Renyi, Wu Peng, Wu Qiong, Jiang Shaotong, and Dong Yiyang. "Microwave-Assisted Extraction Combined with Ultra-High-Performance Liquid Chromatography and Quadrupole/Q-Exactive High-Resolution Mass Spectrometry for the Determination of Main Flavor Substances in Green Tea." Journal of AOAC INTERNATIONAL 103, no. 2 (March 2020): 428–32. http://dx.doi.org/10.5740/jaoacint.19-0265.

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Abstract Background: In order to make up for the efficacy of sensory assessment of green tea quality and taste, main flavor substances should be quantitatively characterized based on efficient extraction and frontier determination scheme. Methods: A new, relatively simple sample preparation and detection workflow has been developed for the quantification and confirmation of flavor substances in green tea by microwave-assisted extraction combined with ultra-high-performance LC and quadrupole/Q-Exactive high-resolution MS system. The method identified main flavor substances (i.e., catechins, free amino acids, and caffeine) that were the main components in the formation of tea taste. After crushing pretreatment, tea was extracted and purified simultaneously in a microwave extraction jar by matrix-dispersed solid-phase extraction. The extracting solution was determined by LC coupled to high-resolution Orbitrap mass spectrometry. Results: In this study, extraction solvent and purification materials were selected, extraction temperature and time were optimized, and the amount and proportion of solid-phase extraction packing were optimized. Conclusions: The method enabled detection of multiple catechins, amino acids, and caffeine in tea by LC coupled to high-resolution Orbitrap MS, and a database of tea flavor substances was established. Highlights: The method could be used for screening and confirmation of the main flavor substances in tea as well as assisting the sensory evaluation to grade the quality of tea.

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Zhou, Jianwen, Caixia Han, Hui Cao, Shoumin Zhen, Zitong Yu, Xiaohui Li, Wujun Ma, and Yueming Yan. "Fast identification of wheat 1BL.1RS translocation by reversed-phase ultra-performance liquid chromatography (RP-UPLC)." Crop and Pasture Science 64, no. 9 (2013): 865. http://dx.doi.org/10.1071/cp13246.

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The 1BL.1RS chromosomal translocation in wheat is the result of replacement of the short arm of chromosome 1B of wheat by the short arm of chromosome 1R of rye, which had been widely used as a parental line in worldwide wheat breeding, resulting in a high percentage of wheat cultivars containing this translocation. A fast and reliable approach to identify this translocation is highly desirable in modern wheat breeding. This study compared reversed-phase ultra-performance liquid chromatography (RP-UPLC), acidic polyacrylamide gel electrophoresis (A-PAGE), liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS), allelic-specific PCR, and reversed-phase high-performance liquid chromatography (RP-HPLC) approaches to identify the 1BL.1RS translocation in 76 bread wheat cultivars. Two gliadin bands in the Gli-B1 region of A-PAGE separation were confirmed by LC-MS/MS to be omega secalins from the 1BL.1RS translocation, and they can be used as reliable protein markers for identifying the translocation. A few specific minor peaks eluted at 12–13 min on the RP-UPLC patterns can readily differentiate the 1BL.1RS translocation. Of the 76 wheat cultivars tested, 40 were identified as carrying the 1BL.1RS translocation by RP-UPLC, which was consistent with the results of A-PAGE, HPLC, and PCR. Compared with other established methods, RP-UPLC showed a clear advantage in fast identification of the 1BL.1RS translocation with higher reliability and lower costs, and it is therefore ideal for large-scale screening of the 1BL.1RS translocation in wheat breeding.

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Li, Jian, Junmei Ma, Yan Zhang, and Lei Zheng. "Determination of 4 psychoactive substances in tea using ultra high performance liquid chromatography combined with the quadrupole time-of-flight mass spectrometry." Analytical Methods 12, no. 40 (2020): 4878–84. http://dx.doi.org/10.1039/d0ay01535k.

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In this study, a method for the qualification and quantification of 4 psychoactive substances in tea using ultra high performance liquid chromatography coupled with the quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF/MS) has been developed.

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Kosicka, Katarzyna, Anna Siemiątkowska, Agata Szpera-Goździewicz, Mariola Krzyścin, Grzegorz Bręborowicz, and Franciszek Główka. "High-performance liquid chromatography methods for the analysis of endogenous cortisol and cortisone in human urine: comparison of mass spectrometry and fluorescence detection." Annals of Clinical Biochemistry: International Journal of Laboratory Medicine 56, no. 1 (June 25, 2018): 82–89. http://dx.doi.org/10.1177/0004563218783789.

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Background The analysis of steroids in biological matrices is challenging. One can apply immunoassay as well as gas and liquid chromatography with various types of detection, depending on the available equipment and the experience of the analyst. The question is how the methods are interchangeable between themselves. Doubts were reported having compared immunoassays and chromatography-mass spectrometry, but there are scarce data on chromatographic methods with detection types other than mass spectrometry. Methods Here, we present the detailed comparison of two liquid chromatographic methods for the determination of free urinary cortisol and cortisone: one with fluorescence detection (high-performance liquid chromatography [HPLC-FLD]) and the other with tandem mass spectrometry (HPLC-MS/MS). The comparison was made with 199 human urine samples. The data analysis included Passing–Bablok and Deming regression, Bland–Altman test, Wilcoxon test, mountain plot and Lin’s concordance correlation coefficient. Results The validation data indicated that both methods met the requirements of the European Medicines Agency. However, the statistical analysis revealed the systematic bias between the two assays. The Passing–Bablok and the Deming tests showed that the HPLC-FLD method overestimated results for cortisol and underestimated measurements for cortisone. The Bland–Altman analysis estimated the mean differences between the methods: 18.8 nmol/L for cortisol and −16.9 nmol/L for cortisone measurement. Conclusions Both methods’ results led to the same conclusion in observational studies, but the techniques are not interchangeable. The literature data, the observations from the clinical setting and our experience clearly indicate that the future of steroid measurements will belong to chromatography coupled with mass spectrometry.

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Wongchang, Thamrong, Markus Winterberg, Joel Tarning, Natthida Sriboonvorakul, Sant Muangnoicharoen, and Daniel Blessborn. "Determination of ceftriaxone in human plasma using liquid chromatography–tandem mass spectrometry." Wellcome Open Research 4 (September 3, 2021): 47. http://dx.doi.org/10.12688/wellcomeopenres.15141.2.

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Ceftriaxone is a cephalosporin antibiotic drug used as first-line treatment for a number of bacterial diseases. Ceftriaxone belongs to the third generation of antibiotics and is available as an intramuscular or intravenous injection. Previously published pharmacokinetic studies have used high-performance liquid chromatography coupled with ultraviolet detection (HPLC-UV) for the quantification of ceftriaxone. This study aimed to develop and validate a bioanalytical method for the quantification of ceftriaxone in human plasma using liquid chromatography followed by tandem mass spectrometry (LC-MS/MS). Sample preparation was performed by protein precipitation of 100 µl plasma sample in combination with phospholipid-removal techniques to minimize matrix interferences. The chromatographic separation was performed on an Agilent Zorbax Eclipse Plus C18 column with 10 mM ammonium formate containing 2% formic acid: acetonitrile as mobile phase at a flow rate of 0.4 ml/min with a total run time of 10 minutes. Both the analyte and cefotaxime (internal standard) were quantified using the positive electrospray ionization (ESI) mode and selected reaction monitoring (SRM) for the precursor-product ion transitions m/z 555.0→396.1 for ceftriaxone and 456.0→324.0 for cefotaxime. The method was validated over the concentration range of 1.01-200 μg/ml. Calibration response showed good linearity (correlation coefficient > 0.99) and matrix effects were within the ±15% limit in 6 different lots of sodium heparin plasma tested. However, citrate phosphate dextrose plasma resulted in a clear matrix enhancement of 24% at the low concentration level, which was not compensated for by the internal standard. Different anticoagulants (EDTA, heparin and citrate phosphate dextrose) also showed differences in recovery. Thus, it is important to use the same anticoagulant in calibration curves and clinical samples for analysis. The intra-assay and inter-assay precision were less than 5% and 10%, respectively, and therefore well within standard regulatory acceptance criterion of ±15%.

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Palomo-Siguero, Maria, Maria Isabel López-Heras, Carmen Cámara, and Yolanda Madrid. "Accumulation and biotransformation of chitosan-modified selenium nanoparticles in exposed radish (Raphanus sativus)." Journal of Analytical Atomic Spectrometry 30, no. 6 (2015): 1237–44. http://dx.doi.org/10.1039/c4ja00407h.

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Biotransformation of chitosan-modified SeNPs (CS-SeNPs) in radish plants was investigated by using high performance liquid chromatography (HPLC) and asymmetrical flow field flow fractionation (AF⁴) on line coupled to inductively coupled plasma mass spectrometry (ICP-MS) as well as TEM.

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Gallelli, Luca, Andzelika Michniewicz, Erika Cione, Aida Squillace, Manuela Colosimo, Corrado Pelaia, Alessia Fazio, et al. "25-Hydroxy Vitamin D Detection Using Different Analytic Methods in Patients with Migraine." Journal of Clinical Medicine 8, no. 6 (June 22, 2019): 895. http://dx.doi.org/10.3390/jcm8060895.

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Objectives: The aim of this study was to evaluate the performance of different analytic methods, such as liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS), high-performance liquid chromatography-ultraviolet (HPLC-UV), enzyme-linked immunosorbent assay (EIA), and chemiluminescence immunoassays (CLIA), in order to highlight whether or not there is relative superiority amongst the assays. We analyzed two groups of subjects suffering from headache and two groups of healthy subjects. Design and Methods: We performed a prospective, single-blind single-center control-group study on 220 subjects with migraine. Subjects of both sexes >10 years old and with 12 months’ history of migraine were eligible for the study. As a control group, 120 healthy subjects were chosen by their family physician. Results: LC-MS/MS evaluation documented that in all enrolled subjects (migraine and control groups), the serum vitamin D3 levels were lower with respect to the normal range (30–100 ng/mL), with a mean value of 15.4 ng/mL, without difference between sex. The mean values measured using HPLC-UV, EIA, and CLIA tests such as Liaison® and Architect® did not show significant differences compared to the values obtained using LC-MS/MS. Conclusions: In conclusion, the population generally has low values of the vitamin D3 hormone, and the suggested range should probably be revised. HPLC-UV and CLIA were found to have appropriate analytical values compared to the reference method (LC-MS/MS), so it is possible to suggest their routine use to optimize care.

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Journal articles on the topic 'High Performance liquid chromatography coupled with mass spectrometry (LC-MS)'

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