Journal articles: 'Hyphenated HPLC'

1

S, Thangadurai, B. Sithi Asma, A. Palanimurugan, and A. Cyril. "A Forensic Appraisal of Neoteric Hyphenated Techniques for Separation and Detection of Narcotic Drugs." International Journal of Forensic Sciences 10, no. 1 (2025): 1–17. https://doi.org/10.23880/ijfsc-16000430.

Full text

Abstract:

Narcotic drugs are traditionally been identified on basis of chromatographic-hyphenated techniques in instrumental analysis. Nowadays, contemporary neoteric chromatographic hyphenated techniques have received ever-increasing attention because the principal means to unravel complex analytical problems. A legal examination is a term articulated for examination of all sorts of violations that leads to the prove for any sort of wrong doing as a conclusion of the suspect. Forensic laboratories drugs are identified and separated by TLC, HPLC, HPTLC, GC, LC and known hyphenated techniques which are like HPLC-MS, HPTLC-MS, GC-MS, and LC-MS-MS etc. give reliable and confirmatory leads to drugs identification. HPLC-MS is more preferred method for separation and detection of narcotic drugs. The drawback of HPLC which it requires more solvent as compared to HPTLC. These techniques provide efficient, quick and straightforward method for detection and separation of narcotic drugs and psychotropic substances (NDPS). Analytical chemists face a challenging task in separating, identifying, and determining illicit drugs in pills and biological fluids. There is an increasing need to create advanced methodologies to reduce analysis time, improve sensitivity, and progress towards green chemistry. The hyphenated techniques help in low level detection, highly specific detection, and precise and accurate results for the forensic investigations.

APA, Harvard, Vancouver, ISO, and other styles

2

Komal, Zade* Mrunali Ahirrao Madhuri Shirsath Tufail Dana M. B. Nikam. "HPLC and its Hyphenated Techniques: Review." International Journal of Scientific Research and Technology 2, no. 5 (2025): 584–99. https://doi.org/10.5281/zenodo.15529234.

Full text

Abstract:

High Performance Liquid Chromatography (HPLC) is a precise analytical technique used to separate, identify, and quantify components within complex mixtures. Developed in the late 1960s, it operates by pumping a liquid mobile phase under high pressure (50–350 bars) through a column packed with solid adsorbents like silica or polymers, which interact differently with each sample component to achieve separation. HPLC is favored in pharmaceuticals, biotechnology, environmental testing, and food industries for its speed, sensitivity, and high resolution. Hyphenated techniques in liquid chromatography combine chromatography with spectroscopic methods, a concept introduced by Hirsch Feld in 1980. These integrated systems, such as LC-MS, LC-NMR, and LC-FTIR, use appropriate interfaces to enable simultaneous separation and detailed detection, offering enhanced qualitative and quantitative analysis. These approaches are crucial in modern drug discovery and chemical analysis, providing comprehensive data in a single run.

APA, Harvard, Vancouver, ISO, and other styles

3

Liu, Zhifu, Zhi Xing, Zhaoyang Li, et al. "The online coupling of high performance liquid chromatography with atomic fluorescence spectrometry based on dielectric barrier discharge induced chemical vapor generation for the speciation of mercury." Journal of Analytical Atomic Spectrometry 32, no. 3 (2017): 678–85. http://dx.doi.org/10.1039/c6ja00421k.

Full text

APA, Harvard, Vancouver, ISO, and other styles

4

Londonio, Agustín, Paul Emir Hasuoka, Pablo Pacheco, Raúl Andrés Gil, and Patricia Smichowski. "Online solid phase extraction-HPLC-ICP-MS system for mercury and methylmercury preconcentration using functionalised carbon nanotubes for their determination in dietary supplements." Journal of Analytical Atomic Spectrometry 33, no. 10 (2018): 1737–44. http://dx.doi.org/10.1039/c8ja00188j.

Full text

APA, Harvard, Vancouver, ISO, and other styles

5

Chindaphan, Kanokporn, Isaya Thaveesangsakulthai, Suchapa Naranaruemol, et al. "Miniaturized electrocoagulation approach for removal of polymeric pigments and selective analysis of non- and mono-hydroxylated phenolic acids in wine with HPLC-UV." RSC Advances 11, no. 11 (2021): 5885–93. http://dx.doi.org/10.1039/d0ra09089a.

Full text

Abstract:

Electrocoagulation (EC) approach was developed to allow fast sample clean-up step prior to selective analysis of non- and mono-hydroxylated phenolic acids in red wine samples with high performance liquid chromatography hyphenated with UV detection (HPLC-UV).

APA, Harvard, Vancouver, ISO, and other styles

6

Ambarsing, P. Rajput, and P. Edlabadkar Aboli. "An Inclusive Review on Analytical Methods for Ritonavir in Various Pharmaceutical and Biological Matrix." Pharmaceutical Methods 8, no. 2 (2017): 01–11. https://doi.org/10.5281/zenodo.14854936.

Full text

Abstract:

Background: Ritonavir (RTV) is an anti-retroviral drug used in the treatment of HIV/ AIDS. Many times, RTV is used alone and in combination with many anti retroviral drugs. So far, around seventy nine analytical methods have been reported for various studies on analysis of RTV in bulk, pharmaceutical formulations and biological fluids. Aim: To summarize the various analytical techniques such as Chromatography, Spectrophotometry; Capillary electrophoresis and also hyphenated techniques such as LC- MS/MS for estimation of Ritonavir. Method: The present article deals with the comprehensive details about the type of various analytical techniques such as Chromatography, Spectrophotometry; Capillary electrophoresis and also hyphenated techniques such as LC- MS/MS, and their applicability in analysis of RTV. These techniques are either explored for the quantification, detection of metabolite and also for stability-studies of the RTV. Conclusion: The present studies revealed that HPLC technique along with the spectro scopic have been most widely explored for the analysis. The investigatory review may provide the comprehensive details to the researchers who are working in the area of analytical research of RTV.

APA, Harvard, Vancouver, ISO, and other styles

7

Adigal, Sphurti S., Sulatha V. Bhandary, Nagaraj Hegde, et al. "Correction: Protein profile analysis of tear fluid with hyphenated HPLC-UV LED-induced fluorescence detection for the diagnosis of dry eye syndrome." RSC Advances 13, no. 39 (2023): 27446. http://dx.doi.org/10.1039/d3ra90084c.

Full text

Abstract:

Correction for ‘Protein profile analysis of tear fluid with hyphenated HPLC-UV LED-induced fluorescence detection for the diagnosis of dry eye syndrome’ by Sphurti S. Adigal et al., RSC Adv., 2023, 13, 22559–22568. https://doi.org/10.1039/D3RA04389D.

APA, Harvard, Vancouver, ISO, and other styles

8

Mandal, Badal Kumar, and Yong-Chien Ling. "Analysis of Chlorophylls/Chlorophyllins in Food Products Using HPLC and HPLC-MS Methods." Molecules 28, no. 10 (2023): 4012. http://dx.doi.org/10.3390/molecules28104012.

Full text

Abstract:

Of the different quality parameters of any food commodity or beverage, color is the most important, attractive and choice-affecting sensory factor to consumers and customers. Nowadays, food industries are interested in making the appearance of their food products attractive and interesting in order to appeal to consumers/customers. Natural green colorants have been accepted universally due to their natural appeal as well as their nontoxic nature to consumers. In addition, several food safety issues mean that natural green colorants are preferable to synthetic food colorants, which are mostly unsafe to the consumers but are less costly, more stable, and create more attractive color hues in food processing. Natural colorants are prone to degradation into numerous fragments during food processing, and thereafter, in storage. Although different hyphenated techniques (especially high-performance liquid chromatography (HPLC), LC-MS/HRMS, and LC/MS-MS are extensively used to characterize all these degradants and fragments, some of them are not responsive to any of these techniques, and some substituents in the tetrapyrrole skeleton are insensitive to these characterization tools. Such circumstances warrant an alternative tool to characterize them accurately for risk assessment and legislation purposes. This review summarizes the different degradants of chlorophylls and chlorophyllins under different conditions, their separation and identification using various hyphenated techniques, national legislation regarding them, and the challenges involved in their analysis. Finally, this review proposes that a non-targeted analysis method that combines HPLC and HR-MS assisted by powerful software tools and a large database could be an effective tool to analyze all possible chlorophyll and chlorophyllin-based colorants and degradants in food products in the future.

APA, Harvard, Vancouver, ISO, and other styles

9

Amir, Mohammad, Puneet Narula, and Farzana Bano. "Analytical Techniques for the Analysis of Lopinavir and Ritonavir in Pharmaceutical Dosage Form and Biological Matrices: A Review." Current Pharmaceutical Analysis 18, no. 4 (2022): 380–414. http://dx.doi.org/10.2174/1573412918666211217145200.

Full text

Abstract:

Background: Lopinavir and Ritonavir are protease inhibitor type of anti-retroviral drugs. Both are used for the treatment of HIV/AIDS. This paper reviews many analytical methods for the analysis of LPV and RTV in pharmaceutical formulations (tablet, capsule, syrup, and bulk) and biological fluids (human plasma, serum, cerebrospinal fluid, rat plasma, and human hair). Objective: The study aims to summarize various analytical techniques, such as chromatography and spectrophotometry, and also hyphenated techniques, such as LC-MS/MS and UPLC-MS, for the analysis of Lopinavir and Ritonavir. Method: The review deals with comprehensive details regarding the type of various analytical techniques, such as spectroscopy (UV), chromatography (RP-HPLC, HPTLC, UPLC), and hyphenated techniques, i.e., LC-MS/MS and UPLC-MS, for the analysis of lopinavir and ritonavir. These techniques are either explored for the quantification and detection of metabolite or for stability studies of the LPV and RTV. Conclusion: The studies presented revealed that the HPLC technique along with spectroscopy have been most widely used for the analysis. Out of the developed methods, hyphenated UPLCMS and LC-MS are very sensitive and help in the easy estimation of drugs compared to other techniques. This review may provide comprehensive details to the researchers working in the area of analytical research of LPV and RTV.

APA, Harvard, Vancouver, ISO, and other styles

10

Peng, Sean X. "Hyphenated HPLC-NMR and its applications in drug discovery." Biomedical Chromatography 14, no. 6 (2000): 430–41. http://dx.doi.org/10.1002/1099-0801(200010)14:6<430::aid-bmc32>3.0.co;2-p.

Full text

APA, Harvard, Vancouver, ISO, and other styles

11

Kumar, Deepak, Amrendra Kumar, Vinay Kumar, et al. "A Comprehensive Review on Analytical Method Development using RP-HPLC and Recent Advances in Pharmaceutical Applications." Journal for Research in Applied Sciences and Biotechnology 2, no. 2 (2023): 53–60. http://dx.doi.org/10.55544/jrasb.2.2.9.

Full text

Abstract:

The analytical technique of choice for separating, identifying, and quantifying complex mixtures is high-performance liquid chromatography (HPLC). Reverse-phase liquid chromatography (RP-HPLC) is the preferred separation mode for high-performance liquid chromatography (HPLC) due to its adaptability and higher selectivity for hydrophobic compounds. This review article discusses the fundamentals of reversed-phase high-performance liquid chromatography (RP-HPLC). This covers the separation principle, various stationary and mobile phase types, and separation-affecting variables. This article highlights the need of developing and testing such methods in addition to outlining the advantages of using RP-HPLC in industries like pharmaceutical, food, and environmental analysis. As examples of more recent advancements in RP-HPLC, new stationary and mobile phases, RP-HPLC downsizing, and hyphenated methods are also discussed. This review article provides a comprehensive tool for designing, refining, and validating RP-HPLC processes.

APA, Harvard, Vancouver, ISO, and other styles

12

Sturm, Sonja, Christina Högner, Christoph Seger, and Hermann Stuppner. "Combining HPLC-DAD-QTOF-MS and HPLC-SPE-NMR to Monitor In Vitro Vitetrifolin D Phase I and II Metabolism." Metabolites 11, no. 8 (2021): 529. http://dx.doi.org/10.3390/metabo11080529.

Full text

Abstract:

By combining HPLC-DAD-QTOF-MS and HPLC-SPE-NMR, the in vitro metabolism of vitetrifolin D, a pharmacologically active key molecule from Vitex agnus-castus in liver cell fractions, was investigated. Twenty-seven phase I and phase II metabolites were tentatively identified from the culture broth by HPLC-DAD-QTOF-MS. The subsequent HPLC-SPE-NMR analysis allowed for the unequivocal structural characterization of nine phase I metabolites. Since the preparative isolation of the metabolites was avoided, the substance input was much lower than in conventional strategies. The study did prove that the use of hyphenated instrumental analysis methodologies allows for the successful performance of in vitro metabolism studies, even if the availability of substances is very limited.

APA, Harvard, Vancouver, ISO, and other styles

13

Shounak, Mande*. "A Review Article on Hyphenated Techniques Used in Analytical Method and Development." International Journal of Pharmaceutical Sciences 3, no. 1 (2025): 2407–17. https://doi.org/10.5281/zenodo.14762916.

Full text

Abstract:

The hyphenated techniques refers to the combination or synthesis of distinct analytical methodologies. Spectroscopic techniques are mostly paired with chromatographic techniques. After that, an interphase will allow the mixture's separated components from the chromatographic approach to enter the spectroscopic technique. In GC-MS After separation from gas chromatography, ionization and mass spectrometry are added to MS. analysis and measurement of the mass-to-charge ratios of the ions that the mass spectrometer generates from each analysis. GC and MS can be connected by a membrane separator, jet/orifice separator, or effusion separator. The analytical flow cell in LC-NMR coupling was originally designed for continuous flow to NMR. But the requirement for thorough structural evaluation of novel products has resulted in the use of LCMS in stopped-flow mode. The use of LC-MS-MS is increasing continuously at a rapid rate. Hyphenated methods like UV-coupled HPLC. The combination of mass spectrometry (LC-UV-MS) with biological screening has proven to be quite beneficial for a quick analysis of products. Hyphenated procedures pertain to the process of separating, identifying, and the hyphenated procedures demonstrate improved sample analysis in terms of specificity, accuracy, and precision. (1).

APA, Harvard, Vancouver, ISO, and other styles

14

Khalid, Sami A. "Decades of Phytochemical Research on African Biodiversity." Natural Product Communications 4, no. 10 (2009): 1934578X0900401. http://dx.doi.org/10.1177/1934578x0900401020.

Full text

Abstract:

This review provides a panoramic view of Prof. Kurt Hostettmann's contribution to the study of African medicinal plants as documented in over 85 publications with collaborators from about a dozen African countries. Many novel bioactive secondary metabolites were isolated, their structures elucidated by hyphenated HPLC techniques and their biological activity determined.

APA, Harvard, Vancouver, ISO, and other styles

15

Szpunar, J., and R. Lobinski. "Species-selective Analysis for Metal - Biomacromolecular Complexes using Hyphenated Techniques." Pure and Applied Chemistry 71, no. 5 (1999): 899–918. http://dx.doi.org/10.1351/pac199971050899.

Full text

Abstract:

Analytical chemistry of metal complexes with biomacromolecules based on the coupling of a high resolution separation technique with an element or species selective detection technique is critically discussed. The role of size-exclusion chromatography (SEC) with on-line atomic spectrometric detection is evaluated for the characterization of the metal distribution among the fractions of different molecular weight. Attention is given to the conditions for the separation of metallated biomacromolecular isoforms and sub-isoforms by anion-exchange and reversed-phase HPLC. Techniques for interfacing chromatography with atomic absorption spectrometry (AAS), inductively coupled plasma atomic emission spectrometry (ICP AES) and ICP mass spectrometry (ICP MS) are assessed. The potential of electrospray (tandem) mass spectrometry for the on-line determination of the molecular mass of the eluting protein is highlighted. Perspectives for capillary zone electrophoresis (CZE), microbore and capillary HPLC with ICP MS and electrospray MS detection for probing metalloproteins are discussed. Applications of hyphenated techniques to the analysis of real-world samples are reviewed.

APA, Harvard, Vancouver, ISO, and other styles

16

Mohammed, Navaziya. "HPLC Hyphenations in Advanced Analytical World." Journal of Physical Chemistry & Biophysics 12, no. 2 (2022): 5. https://doi.org/10.5281/zenodo.14604252.

Full text

Abstract:

Traditional analytical approaches of HPLC found to be insufficient for solving upcoming challenges in species specificity and sensitivity analysis. Modern analytical hybrid techniques which are referred as hyphenations have been introduced from the traditional techniques to overcome the challenges in the analysis of components. Hyphenated approaches combine separation and detection procedures through the use of chromatographic and spectroscopic techniques. The various hyphenations of that are developed until now are LC-MS, LC-NMR, LC-IR, LC-DAD and it also includes multi hyphenations like LC-MS-MS, LC-ESI-MS. These techniques show high specificity and sensitivity. Now-a-days various types of LC-MS systems with various types of interfaces are a commercially available. The application of these hyphenations in many sectors such as forensic science, environment, biotechnology, pharmaceutical field is discussed.

APA, Harvard, Vancouver, ISO, and other styles

17

Stojanović, Jevrem, Jovana Krmar, Ana Protić, Bojana Svrkota, Nevena Đajić, and Biljana Otašević. "Experimental design in HPLC separation of pharmaceuticals." Arhiv za farmaciju 71, no. 4 (2021): 279–301. http://dx.doi.org/10.5937/arhfarm71-32480.

Full text

Abstract:

Design of Experiments (DoE) is an indispensable tool in contemporary drug analysis as it simultaneously balances a number of chromatographic parameters to ensure optimal separation in High Pressure Liquid Chromatography (HPLC). This manuscript briefly outlines the theoretical background of the DOE and provides step-by-step instruction for its implementation in HPLC pharmaceutical practice. It particularly discusses the classification of various design types and their possibilities to rationalize the different stages of HPLC method development workflow, such as the selection of the most influential factors, factors optimization and assessment of the method robustness. Additionally, the application of the DOE-based Analytical Quality by Design (AQbD) concept in the LC method development has been summarized. Recent achievements in the use of DOE in the development of stability-indicating LC and hyphenated LC-MS methods have also been briefly reported. Performing of Quantitative structure retention relationship (QSRR) study enhanced with DOE-based data collection was recomended as a future perspective in description of retention in HPLC system.

APA, Harvard, Vancouver, ISO, and other styles

18

Zsila, F., A. Gergely, P. Horváth, and Gy Szász. "SEPARATION AND IDENTIFICATION OF TOFISOPAM STEREOISOMERS BY HYPHENATED HPLC-CD TECHNIQUE." Journal of Liquid Chromatography & Related Technologies 22, no. 5 (1999): 713–19. http://dx.doi.org/10.1081/jlc-100101693.

Full text

APA, Harvard, Vancouver, ISO, and other styles

19

Anjani, M. Nikhare* R.T. Lohiya S. W. Rangari M. J. Umekar. "A Review on Method Development and Validation." International Journal of Pharmaceutical Sciences 2, no. 11 (2024): 312–18. https://doi.org/10.5281/zenodo.14044901.

Full text

Abstract:

Developing analytical methods and then validating them is a crucial step in the drug discovery process. The absence of an approved analytical technique will prevent the medicine from reaching the market, even though it has good potency. As a result, the quality and safety of the medication.  In order to assess the stability of the drugs in the presence of excipients and other stress conditions encountered during their shelf life period, this review's primary goal is to provide an overview of the traditional and innovative methods available for the analysis of drugs in their raw material and formulated forms. LC-MS, LC-MS-MS, LC NMR-MS, GC-MS, and LC-MS are some of the hyphenated techniques for drug analysis and impurity profiling that are clarified by the review study.

APA, Harvard, Vancouver, ISO, and other styles

20

Swati, Dubey Ravindra Kumar Pandey Shiv Shankar Shukla*. "IMPURITY PROFILING AND DRUG CHARACTERIZATION: BACKDROP AND APPROACH." INDO AMERICAN JOURNAL OF PHARMACEUTICAL SCIENCES 05, no. 04 (2018): 2499–515. https://doi.org/10.5281/zenodo.1218717.

Full text

Abstract:

Impurities are always an ‘essential evil’, that will however be present with the drug products with but with the dawn of more safety based limits for controlling the related impure substances (ICH Q3A-D and M7) it can be relied that such controlling authorities will better comprehend the course of action and consent to an appropriate tolerable limits to possibility (commercial and patient needs).Impurity produced either through formulation or in the lead ageing of both API’s and formulated products in medicines. These unwanted chemicals, present even in small amount, may influence the efficacy and safety of the pharmaceutical products. Any substance/ unwanted chemical that is present in the active ingredient or drug substance which affects the purity of the material is not always inferior in quality. From the point of view of its applicability, the drug substance is compromised in terms of purity even if it contains another material with superior pharmacological or toxicological properties. Highly sophisticated instrumentation, viz MS attached to a Gas Chromatography or HPLC, LC-MS and other hyphenated and double hyphenated techniques are foreseeable tools in the identification of minor components (drugs, impurities, degradation products, metabolites) in various matrices. Keywords: Analytical Method Validation, Forced degradation studies, ICH Guidelines Impurity profiling, Hyphenated techniques.

APA, Harvard, Vancouver, ISO, and other styles

21

Marcinkowska, Monika, and Danuta Barałkiewicz. "Multielemental speciation analysis by advanced hyphenated technique – HPLC/ICP-MS: A review." Talanta 161 (December 2016): 177–204. http://dx.doi.org/10.1016/j.talanta.2016.08.034.

Full text

APA, Harvard, Vancouver, ISO, and other styles

22

Madhuri, R. Shirsath Sonali A. Waghmare And Pradyumna P. Ige. "A Review On Recent Advances In Development Of RP-HPLC Method." International Journal of Pharmaceutical Sciences 2, no. 8 (2024): 2674–82. https://doi.org/10.5281/zenodo.13242715.

Full text

Abstract:

The development and validation of analytical methods play crucial roles in drug discovery, drug development, and the production of different pharmaceutical formulations. A straightforward, accurate, exact, and targeted RP-HPLC approach was created to determine the drug in pharmaceuticals. Because of its greater selectivity and flexibility for hydrophobic substances, reverse-phase liquid chromatography (RP-HPLC) is the separation method of choice for high-performance liquid chromatography (HPLC). The development of RP HPLC methods has advanced significantly in recent years, with new stationary phases, enhanced column technology, and creative optimization techniques among its many achievements. Improvements in selectivity and decreased non-specific adsorption have resulted from these developments, which have also raised speed, resolution, and sensitivity. Furthermore, RP HPLC has been used in many other areas, such as biotechnology, environmental analysis, food and beverage, pharmaceuticals, and forensic science. The development of RP HPLC methods is not without difficulties, despite its many advantages. These difficulties include problems with column stability, sample preparation, and optimization. This article describes new techniques that can be used with the RP-HPLC process to design and produce novel pharmaceuticals. Additionally covered are instances of more current developments in hyphenated methods like RP-HPLC. We intend to stimulate ongoing innovation and advancement in the developing field of pharmacy by examining the most recent developments, applications, and difficulties in the creation of RP-HPLC methods.

APA, Harvard, Vancouver, ISO, and other styles

23

Wei, Ming-Chi, Yu-Chiao Yang, and Show-Jen Hong. "Determination of Oleanolic and Ursolic Acids inHedyotis diffusaUsing Hyphenated Ultrasound-Assisted Supercritical Carbon Dioxide Extraction and Chromatography." Evidence-Based Complementary and Alternative Medicine 2015 (2015): 1–10. http://dx.doi.org/10.1155/2015/450547.

Full text

Abstract:

Oleanolic acid (OA) and ursolic acid (UA) were extracted fromHedyotis diffusausing a hyphenated procedure of ultrasound-assisted and supercritical carbon dioxide (HSC–CO2) extraction at different temperatures, pressures, cosolvent percentages, and SC–CO2flow rates. The results indicated that these parameters significantly affected the extraction yield. The maximal yields of OA (0.917 mg/g of dry plant) and UA (3.540 mg/g of dry plant) were obtained at a dynamic extraction time of 110 min, a static extraction time of 15 min, 28.2 MPa, and 56°C with a 12.5% (v/v) cosolvent (ethanol/water = 82/18, v/v) and SC–CO2flowing at 2.3 mL/min (STP). The extracted yields were then analyzed by high performance liquid chromatography (HPLC) to quantify the OA and UA. The present findings revealed thatH. diffusais a potential source of OA and UA. In addition, using the hyphenated procedure for extraction is a promising and alternative process for recovering OA and UA fromH. diffusaat high concentrations.

APA, Harvard, Vancouver, ISO, and other styles

24

Qian, Zheng-Ming, Bo-Wen Fang, Hai-Ming Chen, et al. "Online Liquid Microextraction Coupled with HPLC-ABTS for Rapid Screening of Natural Antioxidants: Case Study of Three Different Teas." Journal of Chromatographic Science 58, no. 9 (2020): 875–79. http://dx.doi.org/10.1093/chromsci/bmaa047.

Full text

Abstract:

Abstract In the present study, an online liquid extraction coupled with high-performance liquid chromatography-2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (HPLC-ABTS) system for rapid screening of antioxidants in tea samples was proposed. As an example, the tea samples were firstly extracted by online HPLC extractor with mobile phase at 70°C, then the hyphenated HPLC-ABTS was used for the chromatographic separation on a Poroshell EC C18 column by 0.3% aqueous formic acid and acetonitrile with a gradient elution at 1.5 mL·min−1, and the UV and antioxidant chromatograms with detection wavelengths at 270 nm and 750 nm were recorded, respectively. The established system integrated the processes of online HPLC sample extraction, HPLC separation and online antioxidants detection, the total analysis time of which was &lt;20 min. The developed method was successfully applied to samples of green tea, oolong tea and black tea. As a result, 11 antioxidants were found in tea samples, including gallocatechin, epigallocatechin, catechin, chlorogenic acid, epicatechin, epigallocatechingallate, epicatechingallate, rutin, 1,4,6-trigalloylglucose, quercetin-3-glycoside and kaempferol-3-glucoside. The combined online liquid microextraction and online HPLC-ABTS method is a rapid and green approach for the quality evaluation of tea.

APA, Harvard, Vancouver, ISO, and other styles

25

Proch, Jędrzej. "UKŁADY ŁĄCZONE OPARTE NA DETEKCJI PRZY UŻYCIU OPTYCZNEJ SPEKTROMETRII EMISYJNEJ W OZNACZANIU FORM METALI I METALOIDÓW." Wiadomości Chemiczne 79, no. 1 (2023): 61–79. https://doi.org/10.53584/wiadchem.2025.1.4.

Full text

Abstract:

Hydride generation (HG) has become a widely used technique for efficient analyte introduction in optical emission spectrometry, although only few hyphenated systems using this technique have been developed. It was decided to fill this gap using a modified spray chamber that allows with conventional nebulizer and/or as hydride generator, i.e. the Multi-mode Sample Introduction System (MSIS). The MSIS unit was used as an interface between high-performance liquid chromatography (HPLC) and inductively coupled plasma optical emission spectrometry (ICP OES) or microwave induced plasma optical emission spectrometry (MIP OES). In this way, hyphenated techniques were designed, based on three modes of operation of the MSIS chamber: (1) hydride generation for the determination of metalloid species occurring as anions and forming volatile hydrides, (2) conventional sputtering for the determination of metal species occurring as cations, and (3) dual mode for the simultaneous determination of metal and metalloid species occurring as cations and anions. The article is based on the doctoral dissertation of Jędrzej Proch entitled: "Hyphenated systems based on detection by optical emission spectrometry in determination of metals and metalloids species”, distinguished by the Discipline Council of Chemical Sciences at Adam Mickiewicz University and awarded by the Committee of Analytical Chemistry of the Polish Academy of Sciences in 2024 in the competition for the best doctoral dissertation in analytical spectrometry, the prize funded by MS Spektrum.

APA, Harvard, Vancouver, ISO, and other styles

26

Kowalski, Damian, Ewa Poboży, and Marek Trojanowicz. "Flow-Injection Preconcentration of Chloramphenicol Using Molecularly Imprinted Polymer for HPLC Determination in Environmental Samples." Journal of Automated Methods and Management in Chemistry 2011 (2011): 1–10. http://dx.doi.org/10.1155/2011/143416.

Full text

Abstract:

The residue of antibiotic chloramphenicol (CAP) is important issue for food quality control and also for the environmental monitoring. It is banned for use in food-producing animals and has very limited use in human medicine, because of its severe impact on human health. Determination of trace level of CAP in environmental samples requires a very sensitive analytical method and efficient preconcentration procedure. CAP can be efficiently preconcentrated in flow-injection system using flow-through reactor packed with molecularly imprinted polymer (MIP), but determination of CAP in eluate from MIP requires the application of chromatographic separation, which was made in reversed-phase HPLC system with UV detection. In optimized conditions the limit of detection for 100 mL sample in HPLC with offline preconcentration on MIP was evaluated as 0.66 mg/L. In hyphenated FIA-HPLC system with zone sampling the LOD for developed method was evaluated as 15 ng/L, which indicates the possibility of using it for analysis of environmental samples.

APA, Harvard, Vancouver, ISO, and other styles

27

Sch�ppenthau, J�rg, and Lothar Dunemann. "Hyphenated HPLC/ICP-MS and HPLC/ICP-OES techniques for the characterization of metal and non-metal species." Fresenius' Journal of Analytical Chemistry 349, no. 12 (1994): 794–99. http://dx.doi.org/10.1007/bf00323108.

Full text

APA, Harvard, Vancouver, ISO, and other styles

28

Sharma, Hemraj, Hari Prasad Sapkota, and Nim Bahadur Dangi. "A Brief Review of Analytical Methods for the Estimation of Allopurinol in Pharmaceutical Formulation and Biological Matrices." International Journal of Analytical Chemistry 2021 (June 5, 2021): 1–12. http://dx.doi.org/10.1155/2021/5558651.

Full text

Abstract:

This review article represents the collection and discussion of various analytical methods available in the literature for the determination of allopurinol (ALLP) in pharmaceutical and biological samples consisting of HPLC, UV-visible method, near-IR spectroscopy, spectrofluorometry, capillary electrophoresis, polarography, voltammetry, and hyphenated techniques such as LC-MS, LC-MS/MS, UPLC-MS/MS, and GC-MS. The anticipated review provides details about the comparative utilization of various analytical techniques for the determination of ALLP. The present review article can be effectively explored to conduct future analytical investigation for the estimation of ALLP.

APA, Harvard, Vancouver, ISO, and other styles

29

Lipka, Emmanuelle, and Claude Vaccher. "Quantitative analysis of drugs in biological matrices by HPLC hyphenated to fluorescence detection." Bioanalysis 7, no. 6 (2015): 743–62. http://dx.doi.org/10.4155/bio.15.20.

Full text

APA, Harvard, Vancouver, ISO, and other styles

30

Mazzucotelli, Ambrogio, Valter Bavastello, Emanuele Magi, Paola Rivaro, and Carlo Tomba. "Analysis of gadolinium polyaminopolycarboxylic complexes by HPLC–ultrasonic nebulizer–ICP-AES hyphenated technique." Anal. Proc. 32, no. 5 (1995): 165–67. http://dx.doi.org/10.1039/ai9953200165.

Full text

APA, Harvard, Vancouver, ISO, and other styles

31

Tang, Huiru, Chaoni Xiao, and Yulan Wang. "Important roles of the hyphenated HPLC-DAD-MS-SPE-NMR technique in metabonomics." Magnetic Resonance in Chemistry 47, S1 (2009): S157—S162. http://dx.doi.org/10.1002/mrc.2513.

Full text

APA, Harvard, Vancouver, ISO, and other styles

32

Ogrodowczyk, Magdalena, Katarzyna Dettlaff, Piotr Kachlicki, and Barbara Marciniec. "Identification of Radiodegradation Products of Acebutolol and Alprenolol by HPLC/MS/MS." Journal of AOAC INTERNATIONAL 98, no. 1 (2015): 46–50. http://dx.doi.org/10.5740/jaoacint.14-096.

Full text

Abstract:

Abstract Two therapeutically active compounds from the group of β-blockers, acebutolol (AC) and alprenolol (AL), in solid form were subjected to ionizing radiation emitted by a beam of high energy electrons from an accelerator with a standard sterilization dose of 25 kGy and in higher doses of 50–400 kGy. The effects of irradiation were detected by chromatographic methods (TLC, HPLC) and a hyphenated method (HPLC/MS/MS). No significant changes in the physicochemical properties of both compounds studied irradiated with 25 kGy were noted, but upon irradiation with the highest dose (400 kGy) the loss of AC and AL content determined by HPLC was 2.79 and 9.12%, respectively. The product of AC decomposition and the two products of AL decomposition were separated and identified by HPLC/MS/MS. It has been established that radiodegradation of AC and AL takes place by oxidation, leading to formation of the products of radiolysis, most probably alcohol derivatives of the β-blockers studied. The additional product that appears on radiodegradation of AL is probably formed as a result of two simultaneous reactions: oxidation and CH2 group elimination.

APA, Harvard, Vancouver, ISO, and other styles

33

Adhikari, Rudra Prasad, Samima Nasrin Rahman, Suman Lamichhane, and Aditya Bora. "Overview of Analytical Methods for the Determination of H2 Receptor Blockers: A Review." Journal of Drug Delivery and Therapeutics 13, no. 10 (2023): 137–44. http://dx.doi.org/10.22270/jddt.v13i10.6245.

Full text

Abstract:

Overview of various analytical methods for estimating anti-histaminic (H2 Receptor blockers) drugs, particularly for determining their concentration percentage (assay) by analytical methods developed on analytical instruments i.e., UV visible Spectrophotometer, High-Performance Liquid Chromatography, and Hyphenated techniques. The review includes a literature survey of H2 receptor blocker drugs namely cimetidine (Tagamet), ranitidine (Zantac), famotidine (Pepcid, Pepcid AC), and nizatidine (Axid). The examined literature survey addressed chromatographic (HPLC) and UV visible spectrophotometric methods with LC-MS/MS methods used in pure forms, pharmaceutical formulations, human plasma, and other biological fluids for their estimation. In the case of validation parameters, mostly Linearity, Recovery study, LOD, and LOQ were considered and mentioned. This review helps researchers to get detailed information regarding various analytical methods of development and validation for H2 receptor antagonists. Keywords: H2 Receptor blockers, HPLC, Analytical methods, ranitidine, famotidine, nizatidine.

APA, Harvard, Vancouver, ISO, and other styles

34

Patil, Sheetal Vikas, Anup Kishor Nalawade, Rohit Deepak Nalawade, and Shweta Prashant Ghode. "Aliskiren: analytical review for estimation in pharmaceutical formulations." World Journal of Advanced Research and Reviews 6, no. 1 (2020): 019–24. https://doi.org/10.5281/zenodo.4312514.

Full text

Abstract:

Aliskiren (AL) is classified as angiotensin converting enzyme inhibitors (ACEIs) used as antihypertensive drug it acts by dilating blood vessel. These dilation of blood vessel caused due to the renin inhibition. There have been numerous methods developed so far for quantitative estimation of AL in bulk and pharmaceutical dosage form. Pharmaceutical analytical methods include UV Visible Spectrophotometry, Reversed Phase High Performance Liquid Chromatography and hyphenated techniques like Liquid chromatography- Mass Spectrometry. This review paper includes various publications focuses on advanced analytical methods. The chromatographic methods primarily RP-HPLC and LC-MS found more promising and sensitive compared to other pharmaceutical methods.

APA, Harvard, Vancouver, ISO, and other styles

35

Rodriguez, S., A. Marston, J. L. Wolfender, and K. Hostettmann. "lridoids and Secoiridoids in the Gentianaceae." Current Organic Chemistry 2, no. 6 (1998): 627–48. http://dx.doi.org/10.2174/1385272802666220130082729.

Full text

Abstract:

The iridoids and secoiridoids form the largest class of naturally occurring monoterpenes. They are well represented in the Gentianaceae, a family of annual and perennial herbs, and are responsible for their bitter taste. A number of species have reputed medicinal properties; the biological and pharmacological activities of the constituent iridoids and secoiridoids include cardiovascular, stomachic, choleretic, antihepatotoxic activities and insect attractant and repellant properties. Reference is given to the analytical techniques used for iridoids, with special emphasis on hyphenated techniques involving HPLC. Different categories of iridoids, secoiridoids and their glycosides are also enumerated and their distribution within the Gentianaceae is given.

APA, Harvard, Vancouver, ISO, and other styles

36

Jaya P. Ambhore, Vaibhav S. Adhao, Rameshwar S. Cheke, Rameshwar S. Cheke, Ritesh R. Popat, and Shital J. Gandhi. "Futuristic review on progress in force degradation studies and stability indicating assay method for some antiviral drugs." GSC Biological and Pharmaceutical Sciences 16, no. 1 (2021): 133–49. http://dx.doi.org/10.30574/gscbps.2021.16.1.0172.

Full text

Abstract:

Force degradation studies of drug substance give perceptive knowledge about the intrinsic stability of the molecule as well as possible degradants which formed during the shelf life of drug and thus, aid within the successive development of its stable formulation. A number of analytical methods with hyphenated techniques are required for the identification, determination and characterization of degraded product and impurities produce during different conditions of stress studies; Chromatographic methodology play a vital role in the field of impurity and degradation profiling .This review summarizes the current regulatory requirements guidelines for the laboratory performance of forced degradation and its application for the development of stability indicating method. There are number of strategies have been implemented for the quantitative assessment of antiviral drugs. This study will provide detailed literature on stability- indicating HPLC/ RP-HPLC approaches for the development and validation of various antiviral drugs.

APA, Harvard, Vancouver, ISO, and other styles

37

Jaya, P. Ambhore, S. Adhao Vaibhav, S. Cheke Rameshwar, R. Popat Ritesh, and J. Gandhi Shital. "Futuristic review on progress in force degradation studies and stability indicating assay method for some antiviral drugs." GSC Biological and Pharmaceutical Sciences 16, no. 1 (2021): 133–49. https://doi.org/10.5281/zenodo.5168617.

Full text

Abstract:

Force degradation studies of drug substance give perceptive knowledge about the intrinsic stability of the molecule as well as possible degradants which formed during the shelf life of drug and thus, aid within the successive development of its stable formulation. A number of analytical methods with hyphenated techniques are required for the identification, determination and characterization of degraded product and impurities produce during different conditions of stress studies; Chromatographic methodology play a vital role in the field of impurity and degradation profiling .This review summarizes the current regulatory requirements guidelines for the laboratory performance of forced degradation and its application for the development of stability indicating method. There are number of strategies have been implemented for the quantitative assessment of antiviral drugs. This study will provide detailed literature on stability- indicating HPLC/ RP-HPLC approaches for the development and validation of various antiviral drugs.

APA, Harvard, Vancouver, ISO, and other styles

38

Anwar, Shumaila, Akbar Khan, Mariyum Jamal, and Muhammad Zain Siddiqui. "Review on the modern analytical advancements in impurities testing." Advances in Analytic Science 6, no. 1 (2025): 3159. https://doi.org/10.54517/aas3159.

Full text

Abstract:

<p>Impurities in active pharmaceutical ingredients (APIs) and pharmaceutical drug products (DPs) lead to broader antithetical effects related to drug safety, efficacy, and regulatory compliance. This review discusses organic, elemental, and inorganic impurities, and residual solvents and stresses their impact on the quality of APIs and pharmaceutical DPs regarding patient safety. It endorses immensely developed contemporary analytical techniques like High-performance Liquid Chromatography (HPLC), and Gas Chromatography (GC), for organic impurities and discusses their hyphenated Mass Spectrometry (MS) chromatographic methodologies. Atomic Absorption Spectroscopy (AAS), Inductively Coupled Plasma (ICP) hyphenated with MS, and Optical Emission Spectroscopy (OES) techniques are discussed for mainly improved sensitivity and accuracy in the detection and identification of elemental and inorganic impurities. High-Resolution Mass Spectrometry (HRMS), Supercritical Fluid Chromatography (SFC), and ICP-hyphenated techniques alongside automation are among the emerging technologies that are discussed concerning their impending potential to solve intricacies related to complex drug matrices, challenging regulatory requirements, and new impurity profiles. The review underlines the discussion on harmonized global regulations and affordable access to advanced analytical techniques so that wider adoption is facilitated in the pharmaceutical industry. Imminent prospects are Artificial Intelligence (AI) incorporation, Machine Learning (ML), and green analytical methodologies to overcome the present confinements and to cater to the growing demands of the progressive pharmaceutical sector. This in-depth analysis is intended to help pharmaceutical stakeholders embrace novel impurity management approaches resulting in significantly enhanced drug quality and better healthcare outcomes on a global scale.</p>

APA, Harvard, Vancouver, ISO, and other styles

39

Thummala, Veera Raghava Raju. "Isolation, Identification, and Characterization of One Degradation Product in Ambroxol by HPLC-Hyphenated Techniques." Scientia Pharmaceutica 82, no. 2 (2014): 247–63. http://dx.doi.org/10.3797/scipharm.1310-21.

Full text

APA, Harvard, Vancouver, ISO, and other styles

40

Frankowski, M., A. Zioła-Frankowska, and J. Siepak. "New method for speciation analysis of aluminium fluoride complexes by HPLC–FAAS hyphenated technique." Talanta 80, no. 5 (2010): 2120–26. http://dx.doi.org/10.1016/j.talanta.2009.11.018.

Full text

APA, Harvard, Vancouver, ISO, and other styles

41

Vasu Dev, R., G. Sai Uday Kiran, B. Venkata Subbaiah, et al. "Identification of degradation products in stressed tablets of Rabeprazole sodium by HPLC-hyphenated techniques." Magnetic Resonance in Chemistry 47, no. 5 (2009): 443–48. http://dx.doi.org/10.1002/mrc.2404.

Full text

APA, Harvard, Vancouver, ISO, and other styles

42

Mininel, Francisco José, Carlos Sérgio Leonardo Junior, Lívia Greghi Espanha, et al. "Characterization and Quantification of Compounds in the Hydroalcoholic Extract of the Leaves fromTerminalia catappaLinn. (Combretaceae) and Their Mutagenic Activity." Evidence-Based Complementary and Alternative Medicine 2014 (2014): 1–11. http://dx.doi.org/10.1155/2014/676902.

Full text

Abstract:

Terminaliais a genus of Combretaceous plants widely distributed in tropical and subtropical regions. Thus, the aim of this study was to quantify the majority compounds of the hydroalcoholic extract (7 : 3, v/v) of the leaves fromT. catappaby HPLC-PDA, chemically characterize by hyphenated techniques (HPLC-ESI-IT-MSn) and NMR, and evaluate its mutagenic activity by theSalmonella/microsome assay onS. typhimuriumstrains TA98, TA97a, TA100, and TA102. The quantification of analytes was performed using an external calibration standard. Punicalagin is the most abundant polyphenol found in the leaves. The presence of this compound as a mixture of anomers was confirmed using HPLC-PDA and1H and13C NMR. Mutagenic activity was observed in strains TA100 and TA97a. As the extract is a complex mixture of punicalagin, its derivatives, and several other compounds, the observed mutagenicity may be explained in part by possible synergistic interaction between the compounds present in the extract. These studies show that mutagenic activity ofT. catappain the Ames test can only be observed when measured at high concentrations. However, considering the mutagenic effects observed forT. catappa, this plant should be used cautiously for medicinal purposes.

APA, Harvard, Vancouver, ISO, and other styles

43

G, Preethi, Siva Prasad M., Prachet P., and Rama Rao N. "Analytical Methods for the Estimation of Levothyroxine and Levothyroxine Sodium in Pharmaceutical Formulations – A Review." International Journal of Pharmaceutical Sciences and Nanotechnology(IJPSN) 16, no. 6 (2023): 7104–13. http://dx.doi.org/10.37285/ijpsn.2023.16.6.10.

Full text

Abstract:

Levothyroxine (L-T4) is used in the treatment of hypothyroidism and is a synthetic levoisomer of the thyroid hormone thyroxine produced by the thyroid gland. Levothyroxine sodium (L-T4S) salt has a high clinical utility. There are numerous studies that have been published that describe analytical methods for the estimation of L-T4 and L-T4S in pharmaceutical formulations and also in various biological matrices like blood, plasma, serum, and urine. This review article focused on analytical methods for estimating L-T4 and L-T4S in pharmaceutical formulations such as Thin Layer Chromatography (TLC), UV-visible spectrophotometer, High-Performance Liquid Chromatography (HPLC), Capillary electrophoresis, Luminescence, Sequential Injection Analysis (SIA), Voltammetry, and Hyphenated techniques. All the analytical methods for the estimation of L-T4 and L-T4S are given in tabular form. Out of all the analytical methods reported, HPLC is the most commonly used method for the estimation of L-T4 and L-T4S with optimum separation and resolution.

APA, Harvard, Vancouver, ISO, and other styles

44

Weber, Berthold, Martina Herrmann, Beate Hartmann, Holger Joppe, Claus O. Schmidt, and Heinz-Jürgen Bertram. "HPLC/MS and HPLC/NMR as hyphenated techniques for accelerated characterization of the main constituents in Chamomile (Chamomilla recutita [L.] Rauschert)." European Food Research and Technology 226, no. 4 (2007): 755–60. http://dx.doi.org/10.1007/s00217-007-0587-y.

Full text

APA, Harvard, Vancouver, ISO, and other styles

45

S., J. Momin*1 S. R. Shahi2 L. P. Jain3 N. D. Kulkarni4 S. S. Gotpagar5 R. M. Savakhande6. "A Concise Review on Hyphenated Techniques: Liquid Chromatography Coupled Mass Spectroscopy (Lc-Ms/Ms)." International Journal of Pharmaceutical Sciences 3, no. 2 (2025): 1856–68. https://doi.org/10.5281/zenodo.14913274.

Full text

Abstract:

Hyphenated techniques combine spectroscopic and chromatographic methods like LC/MS for toxicology, drug monitoring, pharmacokinetic studies, and bioanalysis with interfaces like APCI and ESI for natural product analysis. Mass spectroscopy (MS) is an analytical technique used to determine the m/e ratio of charged analytes, calculate particle masses, and reveal chemical structures using ionization sources. HPLC and mass spectrometry coupling is complex due to high vacuum requirements, but interfaces like TSP, CFAB, API, and ESI overcome this, integrating detectors with liquid chromatographic separations. LC-MS is one of the hyphenated analytical methods that combine mass spectrometry and liquid chromatography for complex mixture analysis in biological, environmental, and pharmacological materials. It includes mobile phase reservoirs, pumps, degassers, auto samplers, columns, and detectors, with UV being the most common for stability and sensitivity. During the optimization stage, initial conditions such as resolution, peak shape, plate counts asymmetry, capacity factor, elution time, detection limits, limit of quantification, and overall analyte quantification ability are optimized. LC-MS/MS is a popular bioanalysis method for measuring medication concentrations in biological samples, making it the preferred quantitative analysis method between drug discovery and development. Validation of method by various parameters like accuracy precision etc. Applications of LC-MS in various fields like in structural elucidation.

APA, Harvard, Vancouver, ISO, and other styles

46

Kozak, L., M. Rudnicka, and P. Niedzielski. "Determination of Inorganic Selenium Species in Dietary Supplements by Hyphenated Analytical System HPLC-HG-AAS." Food Analytical Methods 5, no. 6 (2012): 1237–43. http://dx.doi.org/10.1007/s12161-012-9365-y.

Full text

APA, Harvard, Vancouver, ISO, and other styles

47

Ogrodowczyk, Magdalena, Barbara Marciniec, and Piotr Kachlicki. "Spectroscopic analysis of pindolol irradiated in the solid state." Open Chemistry 12, no. 1 (2014): 60–66. http://dx.doi.org/10.2478/s11532-013-0348-7.

Full text

Abstract:

AbstractPindolol ((2RS)-(1-(1H-indol-4-iloxy)-3- [(1-metyloetylo)amino]-2-propanol) in substantia was exposed to ionising radiation emitted by high energy electrons from an accelerator, in the standard sterilisation dose of 25 kGy and in higher doses from the range 50–400 kGy. The effects of irradiation were checked by spectrometric methods (UV, MS, FT-IR, EPR) and hyphenated methods (HPLC-MS) and the results were referred to those obtained for non-irradiated sample. EPR results indicated the presence of free radicals in irradiated samples, in the amount of 1.36 × 1016 spin g−1 for 25 kGy and 3.70×1016 spin g−1 for 400 kGy. The loss of pindolol content determined by HPLC was 1.34% after irradiation with 400 kGy, while the radiolytic yield of the total radiolysis for this dose of irradiation was 2.69×107 mol J−1. By means of HPLC-MS it was possible to separate and identify one product of radiolytic decomposition, which probably is 2-((R)-3-(1H-indol-4-yloxy)-2-hydroxypropylamino)propan-1-ol formed upon oxidation. In the range of sterilisation doses (25–50 kGy), pindolol was found to show high radiochemical stability and would probably be safely sterilised by the standard dose of 25 kGy.

APA, Harvard, Vancouver, ISO, and other styles

48

Lee, Sunmin, Dong-Gu Oh, Digar Singh, et al. "Untargeted Metabolomics Toward Systematic Characterization of Antioxidant Compounds in Betulaceae Family Plant Extracts." Metabolites 9, no. 9 (2019): 186. http://dx.doi.org/10.3390/metabo9090186.

Full text

Abstract:

Plant species have traditionally been revered for their unparalleled pharmacognostic applications. We outline a non-iterative multi-parallel metabolomic-cum-bioassay-guided methodology toward the functional characterization of ethanol extracts from the Betulaceae family plants (n = 10). We performed mass spectrometry (MS)-based multivariate analyses and bioassay-guided (ABTS antioxidant activity and cytoprotective effects against H2O2-induced cell damage) analyses of SPE fractions. A clearly distinct metabolomic pattern coupled with significantly higher bioactivities was observed for 40% methanol SPE eluate. Further, the 40% SPE eluate was subjected to preparative high-performance liquid chromatography (prep-HPLC) analysis, yielding 72 sub-fractions (1 min−1), with the highest antioxidant activities observed for the 15 min and 31 min sub-fractions. We simultaneously performed hyphenated-MS-based metabolite characterization of bioactive components for both the 40% methanol SPE fraction and its prep-HPLC sub-fraction (15 min and 31 min). Altogether, 19 candidate metabolites were mainly observed to contribute toward the observed bioactivities. In particular, ethyl gallate was mainly observed to affect the antioxidant activities of SPE and prep-HPLC fractions of Alnus firma extracts. We propose an integrated metabolomic-cum-bioassay-guided approach for the expeditious selection and characterization of discriminant metabolites with desired phenotypes or bioactivities.

APA, Harvard, Vancouver, ISO, and other styles

49

Haberkorn, Michael, Johannes Frank, Michael Harasek, Johan Nilsson, Thomas Laurell, and Bernhard Lendl. "Flow-through Picoliter Dispenser: A New Approach for Solvent Elimination in FT-IR Spectroscopy." Applied Spectroscopy 56, no. 7 (2002): 902–8. http://dx.doi.org/10.1366/000370202760171581.

Full text

Abstract:

A new interface for FT-IR analysis of liquid samples on the basis of solvent elimination is presented. The approach is based on a piezoactuated flow-through microdispenser, a device built of two microstructured silicon wafers designed for micro-liquid handling. It could be verified during preliminary studies using a sequential injection (SI) system for automated liquid handling that the flow-through microdispenser as a possible interface for flow system–FT-IR analysis has the capability of meeting the demands of hyphenated miniaturized liquid handling systems (e.g., μ-HPLC, microhigh performance liquid chromatography), as it successfully provides highly stable, reliable and reproducible operating conditions for liquid handling in the picoliter range. Moreover, an increase in sensitivity for FT-IR measurements could be achieved, lowering the mass detection limit of sugars (such as the investigated sucrose) to 53 picograms. As is demonstrated on the example of an HPLC separation of a mixture of glucose and fructose, interfacing LC systems to FT-IR using a piezoactuated flow-through microdispenser is a feasible and promising approach.

APA, Harvard, Vancouver, ISO, and other styles

50

Veizerová, L., J. Piešťanský, K. Maráková, et al. "Comparison of column-coupled electrophoresis with liquid chromatography methods in food analysis of quinine." Acta Facultatis Pharmaceuticae Universitatis Comenianae 59, no. 1 (2012): 67–80. http://dx.doi.org/10.2478/v10219-012-0011-y.

Full text

Abstract:

Comparison of column-coupled electrophoresis with liquid chromatography methods in food analysis of quinineComparison of column-coupled electrophoresis with liquid chromatography methods in food analysis of quinine (QUI) is presented in this work. The capillary isotachophoresis (CITP) on-line coupled with capillary zone electrophoresis (CZE) and hyphenated with fibre-based spectrophotometric diode array detection (DAD) was compared with, (i) high performance liquid chromatography (HPLC) method with DAD detection, and (ii) HPLC method with fluorescence detection (FD). These methods were compared through their performance parameters and determined concentrations of QUI in beverages. The concentrations of QUI in two selected bitter drinks determined by the CITP-CZE-DAD method were in a good accordance with the HPLC-DAD and HPLC-FD methods. In addition, the electrophoretic method, as well as the chromatographic methods, was able to separate potential QUI related impurities from the QUI peak. The CITP-CZE-DAD method provided excellent performance parameters that were comparable (precision, accuracy, LOD, robustness) or even better (separation efficiency) than those ones provided by the chromatographic methods. Moreover, the effectivity of the electrophoresis method was higher when considering cost of analysis (equipment, consumption of separation systems), environmental aspects (organicvs. aqueous solvents), on-line sample pretreatment (CITP preconcentration and sample clean-up suitable also for the more complex matrices). Considering these findings, CITP-CZE-DAD was approved as a routine automatized method for the highly reliable quality food control.

APA, Harvard, Vancouver, ISO, and other styles

Journal articles on the topic 'Hyphenated HPLC'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles