Journal articles: 'Portable liquid chromatography'

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Sharma, Sonika, Alex Plistil, Robert S. Simpson, Kun Liu, Paul B. Farnsworth, Stanley D. Stearns, and Milton L. Lee. "Instrumentation for hand-portable liquid chromatography." Journal of Chromatography A 1327 (January 2014): 80–89. http://dx.doi.org/10.1016/j.chroma.2013.12.059.

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Soto, Camila, Henry Daniel Ponce-Rodríguez, Jorge Verdú-Andrés, Pilar Campíns-Falcó, and Rosa Herráez-Hernández. "Hand-Portable Miniaturized Liquid Chromatography for the Determination of Chlorogenic Acids in Dietary Supplements." Antioxidants 11, no. 12 (December 5, 2022): 2408. http://dx.doi.org/10.3390/antiox11122408.

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With the explosive growth of the dietary supplements industry, new demands have emerged that cannot be faced with the sophisticated instrumentation available in well-equipped laboratories. In particular, there is a demand for simplified and easy-to-use instruments, capable of providing results in short times of analysis. In this study, a hand-portable miniaturized liquid chromatograph (portable LC) has been tested for the determination of chlorogenic acids (CGAs) in products intended to supplement the diet and elaborated with green coffee extracts. CGAs offer several health benefits due to their antioxidant properties, and an increasing number of dietary supplements are marketed with claimed high contents of these compounds. The results obtained with the proposed portable LC approach have been compared with those obtained with two other miniaturized benchtop liquid chromatography instruments, namely, a capillary liquid chromatograph (capLC) and a nano liquid chromatograph (nanoLC). Although compared with the methods that used the benchtop instruments, the sensitivity attainable was lower, the portable LC instrument provided a comparable analytical performance for the quantification of the main GCAs at low mg g−1 levels, and it was clearly superior in terms of speed. The proposed portable LC-based method can be applied to assess the content and distribution profile of the predominant CGAs in this kind of dietary supplement. It can be also used to estimate the antioxidant power due to CGAs, as well as their preservation state.

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Sharma, Sonika, Alex Plistil, Hal E. Barnett, H. Dennis Tolley, Paul B. Farnsworth, Stanley D. Stearns, and Milton L. Lee. "Hand-Portable Gradient Capillary Liquid Chromatography Pumping System." Analytical Chemistry 87, no. 20 (September 29, 2015): 10457–61. http://dx.doi.org/10.1021/acs.analchem.5b02583.

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Chatzimichail, Stelios, Duncan Casey, and Ali Salehi-Reyhani. "Zero electrical power pump for portable high-performance liquid chromatography." Analyst 144, no. 21 (2019): 6207–13. http://dx.doi.org/10.1039/c9an01302d.

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Foster, Samuel W., Xiaofeng Xie, Michelle Pham, Paul A. Peaden, Leena M. Patil, Luke T. Tolley, Paul B. Farnsworth, H. Dennis Tolley, Milton L. Lee, and James P. Grinias. "Portable capillary liquid chromatography for pharmaceutical and illicit drug analysis." Journal of Separation Science 43, no. 9-10 (February 5, 2020): 1623–27. http://dx.doi.org/10.1002/jssc.201901276.

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Rahimi, Faraz, Stelios Chatzimichail, Aliyah Saifuddin, Andrew J. Surman, Simon D. Taylor-Robinson, and Ali Salehi-Reyhani. "A Review of Portable High-Performance Liquid Chromatography: the Future of the Field?" Chromatographia 83, no. 10 (August 15, 2020): 1165–95. http://dx.doi.org/10.1007/s10337-020-03944-6.

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Abstract There is a growing need for chemical analyses to be performed in the field, at the point of need. Tools and techniques often found in analytical chemistry laboratories are necessary in performing these analyses, yet have, historically, been unable to do so owing to their size, cost and complexity. Technical advances in miniaturisation and liquid chromatography are enabling the translation of these techniques out of the laboratory, and into the field. Here we examine the advances that are enabling portable liquid chromatography (LC). We explore the evolution of portable instrumentation from its inception to the most recent advances, highlighting the trends in the field and discussing the necessary criteria for developing in-field solutions. While instrumentation is becoming more capable it has yet to find adoption outside of research.

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Jornet-Martínez, N., R. Herráez-Hernández, and P. Campíns-Falcó. "Scopolamine analysis in beverages: Bicolorimetric device vs portable nano liquid chromatography." Talanta 232 (September 2021): 122406. http://dx.doi.org/10.1016/j.talanta.2021.122406.

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Soto, C., H. D. Ponce-Rodríguez, J. Verdú-Andrés, R. Herráez-Hernández, and P. Campíns-Falcó. "Determination of caffeine in dietary supplements by miniaturized portable liquid chromatography." Journal of Chromatography A 1664 (February 2022): 462770. http://dx.doi.org/10.1016/j.chroma.2021.462770.

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Li, Ding, Haiyan Chen, Shuang Ren, Yanfang Zhang, Yang Yang, and Honglong Chang. "Portable liquid chromatography for point-of-care testing of glycated haemoglobin." Sensors and Actuators B: Chemical 305 (February 2020): 127484. http://dx.doi.org/10.1016/j.snb.2019.127484.

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Pham, Michelle, Samuel W. Foster, Sangeeta Kurre, Rebecca A. Hunter, and James P. Grinias. "Use of Portable Capillary Liquid Chromatography for Common Educational Demonstrations Involving Separations." Journal of Chemical Education 98, no. 7 (June 29, 2021): 2444–48. http://dx.doi.org/10.1021/acs.jchemed.1c00342.

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Li, Yan, Kirsten Pace, Pavel N. Nesterenko, Brett Paull, Roger Stanley, and Mirek Macka. "Miniaturised electrically actuated high pressure injection valve for portable capillary liquid chromatography." Talanta 180 (April 2018): 32–35. http://dx.doi.org/10.1016/j.talanta.2017.11.061.

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Coates, Lewellwyn J., Shing C. Lam, Andrew A. Gooley, Paul R. Haddad, Brett Paull, and Hans-Jürgen Wirth. "Modular, cost-effective, and portable capillary gradient liquid chromatography system for on-site analysis." Journal of Chromatography A 1626 (August 2020): 461374. http://dx.doi.org/10.1016/j.chroma.2020.461374.

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Nelson, Mary Anne, Arther Gates, Maud Dodlinger, and David S. Hage. "Development of a Portable Immunoextraction-Reversed-Phase Liquid Chromatography System for Field Studies of Herbicide Residues." Analytical Chemistry 76, no. 3 (February 2004): 805–13. http://dx.doi.org/10.1021/ac030298m.

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Laillou, Arnaud, Cécile Renaud, Jacques Berger, Regina Moench-Pfanner, Laura Fontan, and Sylvie Avallone. "Assessment of a Portable Device to Quantify Vitamin A in Fortified Foods (Flour, Sugar, and Milk) for Quality Control." Food and Nutrition Bulletin 35, no. 4 (December 2014): 449–57. http://dx.doi.org/10.1177/156482651403500407.

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Background Simple-to-use quantitative methods are needed to check the adequacy of vitamin A fortification levels. Objective To assess the capacity of a portable fluorometer (iCheck FLUORO) and its test kit vials (iEx Mila) to quantify retinyl palmitate in fortified milks, flours (wheat, maize), and sugar. Methods The portable fluorometer was assessed in a three-step procedure to determine its working range and linearity, intra-assay precision, and interperson precision. Measurements were compared with the results obtained by high-performance liquid chromatography (HPLC), commonly regarded as the standard method for vitamin A analysis. Results The portable fluorometer (iCheck FLUORO) and its test kit vials (iEx Mila) precisely determined the vitamin A contents in fortified flours, sugar, and milks. Its working range was 1 to 10, 0.5 to 3.0, and 5 to 15 mg retinol equivalents (RE) kg−1 for flours (wheat and corn), milks, and sugar, respectively; these values are in accordance with the World Health Organization recommendations for food fortification in least developed countries. The limits of detection are higher than those of HPLC but are all satisfactory (< 1.46 mg RE kg−1). The coefficients of variation within and between observers were satisfactory, especially for sugar and milk. Conclusions The linear relationship between the data from the portable fluorometer and the HPLC data confirms that the portable fluorometer provides a good determination of the vitamin A content of the fortified products in the tested range.

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Zambrzycki, Stephen C., Celine Caillet, Serena Vickers, Marcos Bouza, David V. Donndelinger, Laura C. Geben, Matthew C. Bernier, Paul N. Newton, and Facundo M. Fernández. "Laboratory evaluation of twelve portable devices for medicine quality screening." PLOS Neglected Tropical Diseases 15, no. 9 (September 30, 2021): e0009360. http://dx.doi.org/10.1371/journal.pntd.0009360.

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Background Post-market surveillance is a key regulatory function to prevent substandard and falsified (SF) medicines from being consumed by patients. Field deployable technologies offer the potential for rapid objective screening for SF medicines. Methods and findings We evaluated twelve devices: three near infrared spectrometers (MicroPHAZIR RX, NIR-S-G1, Neospectra 2.5), two Raman spectrometers (Progeny, TruScan RM), one mid-infrared spectrometer (4500a), one disposable colorimetric assay (Paper Analytical Devices, PAD), one disposable immunoassay (Rapid Diagnostic Test, RDT), one portable liquid chromatograph (C-Vue), one microfluidic system (PharmaChk), one mass spectrometer (QDa), and one thin layer chromatography kit (GPHF-Minilab). Each device was tested with a series of field collected medicines (FCM) along with simulated medicines (SIM) formulated in a laboratory. The FCM and SIM ranged from samples with good quality active pharmaceutical ingredient (API) concentrations, reduced concentrations of API (80% and 50% of the API), no API, and the wrong API. All the devices had high sensitivities (91.5 to 100.0%) detecting medicines with no API or the wrong API. However, the sensitivities of each device towards samples with 50% and 80% API varied greatly, from 0% to 100%. The infrared and Raman spectrometers had variable sensitivities for detecting samples with 50% and 80% API (from 5.6% to 50.0%). The devices with the ability to quantitate API (C-Vue, PharmaChk, QDa) had sensitivities ranging from 91.7% to 100% to detect all poor quality samples. The specificity was lower for the quantitative C-Vue, PharmaChk, & QDa (50.0% to 91.7%) than for all the other devices in this study (95.5% to 100%). Conclusions The twelve devices evaluated could detect medicines with the wrong or none of the APIs, consistent with falsified medicines, with high accuracy. However, API quantitation to detect formulations similar to those commonly found in substandards proved more difficult, requiring further technological innovation.

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Geeves, M., and P. Knight. "A cell for X-ray diffraction in liquids under moderate hydrostatic pressure." Journal of Applied Crystallography 22, no. 6 (December 1, 1989): 572–77. http://dx.doi.org/10.1107/s0021889889008277.

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A portable cell is described which allows X-ray diffraction data to be collected from suspensions or mounted specimens in liquid under hydrostatic pressure. Pressure is applied via either an oil pump or a high-performance liquid chromatography pump. The temperature of the cell is controlled by a thermostatted baseplate. X-rays pass through the stainless steel block via windows of Kapton V plastic sheet which will withstand a pressure difference of at least 15 MPa. Distortion of the plastic under pressure increases the liquid path of the X-rays. This distortion can be reduced by stretching over dome-shaped supports. Under these conditions 10 MPa causes a reduction of intensity of between 10 and 50%, depending on window geometry. Specimens can be mounted on a removeable frame, and the solution in the sample chamber can be changed without disassembling the cell. The apparatus has been used successfully to study the low-angle diffraction from muscle.

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Ponce-Rodríguez, H. D., J. Verdú-Andrés, R. Herráez-Hernández, and P. Campíns-Falcó. "Exploring hand-portable nano-liquid chromatography for in place water analysis: Determination of trimethylxanthines as a use case." Science of The Total Environment 747 (December 2020): 140966. http://dx.doi.org/10.1016/j.scitotenv.2020.140966.

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Fujimoto, Takuya, Shogo Kawahara, Yukio Fuchigami, Shoji Shimokawa, Yosuke Nakamura, Kenichi Fukayama, Masao Kamahori, and Shigeyasu Uno. "Portable Electrochemical Sensing System Attached to Smartphones and Its Incorporation with Paper-based Electrochemical Glucose Sensor." International Journal of Electrical and Computer Engineering (IJECE) 7, no. 3 (June 1, 2017): 1423. http://dx.doi.org/10.11591/ijece.v7i3.pp1423-1429.

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This paper described the development of a small and low cost biosensor consisting of a smartphone-based electrochemical biosensor device and a paper-based biosensor. The device harvested power from the smartphone and transferred data through audio jack. We designed CMOS circuits including a power supply circuit, a potentiostat, and a ΔΣ modulator. The fabrication of a paper-based biosensor was simple: the three electrodes were directly drawn on chromatography paper using a carbon pencil. The paper-based biosensor was low cost, disposable, portable and friendly to the environment. The sensing system was designed to perform the chronoamperometry measurement, and the glucose concentration in a liquid specimen was detected. Results showed that the sensing system was capable of measuring the glucose concentration as precisely as expensive equipments.

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Jafari, Safiye, Julian Guercetti, Ariadni Geballa-Koukoula, Aristeidis S. Tsagkaris, Joost L. D. Nelis, M. Pilar Marco, J. Pablo Salvador, et al. "ASSURED Point-of-Need Food Safety Screening: A Critical Assessment of Portable Food Analyzers." Foods 10, no. 6 (June 17, 2021): 1399. http://dx.doi.org/10.3390/foods10061399.

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Standard methods for chemical food safety testing in official laboratories rely largely on liquid or gas chromatography coupled with mass spectrometry. Although these methods are considered the gold standard for quantitative confirmatory analysis, they require sampling, transferring the samples to a central laboratory to be tested by highly trained personnel, and the use of expensive equipment. Therefore, there is an increasing demand for portable and handheld devices to provide rapid, efficient, and on-site screening of food contaminants. Recent technological advancements in the field include smartphone-based, microfluidic chip-based, and paper-based devices integrated with electrochemical and optical biosensing platforms. Furthermore, the potential application of portable mass spectrometers in food testing might bring the confirmatory analysis from the laboratory to the field in the future. Although such systems open new promising possibilities for portable food testing, few of these devices are commercially available. To understand why barriers remain, portable food analyzers reported in the literature over the last ten years were reviewed. To this end, the analytical performance of these devices and the extent they match the World Health Organization benchmark for diagnostic tests, i.e., the Affordable, Sensitive, Specific, User-friendly, Rapid and Robust, Equipment-free, and Deliverable to end-users (ASSURED) criteria, was evaluated critically. A five-star scoring system was used to assess their potential to be implemented as food safety testing systems. The main findings highlight the need for concentrated efforts towards combining the best features of different technologies, to bridge technological gaps and meet commercialization requirements.

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Salih, Mohammed Ali, Dlivan Fattah Aziz, and Salar Ibrahim Ali. "Development and Validation of New High Performance Liquid Chromatography Analytical Technique For Separation of Diclofenac Sodium and Lidocaine Hydrochloride From Ampoule Injection." Kurdistan Journal of Applied Research 5, no. 1 (June 8, 2020): 115–27. http://dx.doi.org/10.24017/science.2020.1.11.

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In the current investigation, a number of chromatographic methods with the accurate, precise and specific criteria have been developed and validated for diclofenac sodium and lidocaine hydrochloride Commitment of their large quantities ampule of pharmaceutical dosage form. The High-Performance Liquid Chromatography (HPLC) system was performed at 25 ° C; with appropriate chromatographic isolation accomplished through the use of Waters Symmetry SB-C7 column with a mobile phase containing 0.1 M sodium acetate and methanol (40:60) (v/v). During development the portable stage was delivered at a stream rate of 1 mL/min, the wavelength was adjusted at 254 nm. First of all, the retention times for diclofenac sodium and lidocaine HCl were about 4.1 and 10.8 min accordingly. A performance and technical demonstration of the suggested Revers phase-HPLC method has been numerically challenged with support to process appropriateness, verticality, scales, simplicity, repeatability, sensitivity, stability, discovery and limits of quantification. In addition, the calibration curves for diclofenac sodium active pharmaceutical ingredient (API) with linear regressions > 0,999895 obtained linear in the distances 1870-5600 μg / mL. Moreover, for determining of lidocaine HCl drug, a range of 500 - 1500 μg/mL of working standard was used, the result showed for lidocain HCl that a linear curve with correlation coefficients of > 0.99980. Finally, the both drugs were isolated and resolute with selective and stable characteristics by the proposed technique. In the conclusion, successful validation of the HPLC approach has been demonstrated with high precision and accuracy for the assessment of both the mixed dosage form type of both diclofenac sodium and lidocaine HCl.

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Dhamdhere Rupali Balasaheb and Vijayalakshmi A. "Improvement of Development and Validation of an RP-HPLC Method for The Fluvastatin Sodium Using QbD Approach and Its Application to Forced Degradation Studies." International Journal of Research in Pharmaceutical Sciences 11, no. 4 (December 14, 2020): 6938–48. http://dx.doi.org/10.26452/ijrps.v11i4.3687.

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The current examination portrays the improvement of the QbD way to deal with Reverse Phase-High Performance Liquid Chromatography (RP-HPLC) framework utilizing Design of Experiments.Each of the three principle parts of the RP-HPLC measure (Buffer pH, Organic Step-percent acetonitrile, Organic Modifier-Methanol) are introduced in a successful test configuration zeroed in on methodical exploring. Through measurable investigation devices, for example, Analysis of Variance (ANOVA) and plots that uncovered the last chromatographic states of the strategy, the criticalness and communication impacts of these boundaries on the reaction factors (maintenance time and following component) were assessed. The chromatographic detachment was accomplished on Thermo Hypersil BDS RP C18 (250 × 4.6 mm, 5μ) section utilizing Buffer (pH 6.8): Acetonitrile (60:40v/v) as portable stage and discovery was finished utilizing Photo-Diode Array (PDA) identifier at 288 nm. The created fluvastatin sodium technique is direct with coefficients of relationship over a scope of 10-80μg/ml. The (R2) estimation of the connection coefficient is 0.999. The percent RSD for the strategy's exactness and accuracy was discovered to be under 2 percent. Investigations of Forced Degradation uncovered that the method was found to show security. The outcomes indicated that the strategy proposed is proper for the exact and precise assurance and detailing of fluvastatin sodium in mass.

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Lee, Nanju A., and Ivan R. Kennedy. "Environmental Monitoring of Pesticides by Immunoanalytical Techniques: Validation, Current Status, and Future Perspectives." Journal of AOAC INTERNATIONAL 84, no. 5 (September 1, 2001): 1393–406. http://dx.doi.org/10.1093/jaoac/84.5.1393.

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Abstract Reliable monitoring technology is an essential component of effective regulation and risk management of environmental contaminants such as pesticides. Most environmental monitoring and analysis is currently conducted using instrumental techniques such as gas–liquid chromatography (GLC) and liquid chromatography (LC). Immunoanalysis provides powerful monitoring techniques that have emerged in the last 3 decades. This paper shows they can deliver rapid, accurate, and relatively inexpensive analysis with high throughput and that have the capability to be field oriented. The technique is versatile in application and can be formatted to suit different purposes such as quantitative analysis or simple “yes/no” tests that are field-portable. While there is a range of opinion on the merits of immunoassays as an analytical tool for pesticides, we suggest that this technology is best considered as complementary to GLC and LC, extending the range of capability for field monitoring. Supporting this view, an increasing number of successful applications of immunoassays to monitoring have been reported in recent years. We also report here the implications of recent developments in the field of immunodiagnostics and their application to monitoring of environmental contaminants. We emphasise that, together with adequate validation by instrumental techniques, immunoassays provide monitoring services yielding realistic and comprehensive data for risk management, allowing decisions on appropriate action by various authorities to be made.

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Stortini, Angela Maria, Maria Antonietta Baldo, Giulia Moro, Federico Polo, and Ligia Maria Moretto. "Bio- and Biomimetic Receptors for Electrochemical Sensing of Heavy Metal Ions." Sensors 20, no. 23 (November 28, 2020): 6800. http://dx.doi.org/10.3390/s20236800.

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Heavy metals ions (HMI), if not properly handled, used and disposed, are a hazard for the ecosystem and pose serious risks for human health. They are counted among the most common environmental pollutants, mainly originating from anthropogenic sources, such as agricultural, industrial and/or domestic effluents, atmospheric emissions, etc. To face this issue, it is necessary not only to determine the origin, distribution and the concentration of HMI but also to rapidly (possibly in real-time) monitor their concentration levels in situ. Therefore, portable, low-cost and high performing analytical tools are urgently needed. Even though in the last decades many analytical tools and methodologies have been designed to this aim, there are still several open challenges. Compared with the traditional analytical techniques, such as atomic absorption/emission spectroscopy, inductively coupled plasma mass spectrometry and/or high-performance liquid chromatography coupled with electrochemical or UV–VIS detectors, bio- and biomimetic electrochemical sensors provide high sensitivity, selectivity and rapid responses within portable and user-friendly devices. In this review, the advances in HMI sensing in the last five years (2016–2020) are addressed. Key examples of bio and biomimetic electrochemical, impedimetric and electrochemiluminescence-based sensors for Hg2+, Cu2+, Pb2+, Cd2+, Cr6+, Zn2+ and Tl+ are described and discussed.

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Kampasakali, Elli, Alexandros Nakas, Dimitrios Mertzanidis, Stella Kokkini, Andreana N. Assimopoulou, and Dimitrios Christofilos. "μ-Raman Determination of Essential Oils’ Constituents from Distillates and Leaf Glands of Origanum Plants." Molecules 28, no. 3 (January 26, 2023): 1221. http://dx.doi.org/10.3390/molecules28031221.

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A novel, inexpensive and simple experimental setup for collecting μ-Raman spectra of volatile liquids in very small quantities was developed. It takes advantage of capillary forces to detain minute volatile liquid volumes. Spectra of volatile and even scattering or absorbing media can be measured more effectively. The method is used to facilitate the collection of intensity-consistent Raman spectra from a series of reference compounds present in Origanum essential oils, in order to quantify their constituents by multiple linear regression. Wild grown Origanum plants, collected from five different regions in Greece and taxonomically identified as O. onites, O. vulgare subsp. hirtum and O. vulgare subsp. vulgare, were appropriately distilled to acquire their essential oils. Comparison of the Raman results with those from headspace gas chromatography–mass spectrometry (HS GC-MS) confirmed the successful relative quantification of the most abundant essential oil constituents, highlighting the similarities and differences of the three Origanum taxa examined. Finally, it is demonstrated that directly measuring the leaf peltate glandular hairs yields exploitable results to identify the main components of the essential oil they contain, underlining the potential of in situ (field or industry) measurements utilizing microscope-equipped portable Raman spectrometers.

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Ojo, Abiodun Ayodele, Akanji Raji Mubarak, Amos Onasanya, Jonathan Johnson, Ezekiel Adewole, and Olajumoke Tolulope Idowu. "Organic Compound Composition in Sachet and Bottled Water Portable Produced in Southwest Ado Ekiti, Nigeria." ABUAD International Journal of Natural and Applied Sciences 2, no. 2 (September 5, 2022): 59–65. http://dx.doi.org/10.53982/aijnas.2022.0202.02-j.

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Organic pollutants are pollutants that are organic in nature, basically containing carbon covalently bonded with other elements. They are known to be toxic or carcinogenic in nature. Their presence in water in large quantity causes considerable and widespread concern. Ten water samples -sachets and bottles, were bought from different potable water producing plants in Ado-Ekiti environs. By using a separatory funnel with liquid-liquid extraction system of 50mL:50mL n-Hexane: Dichloromethane, organic contaminants were extracted from the water samples. These samples were analyzed using ultra violet-visible spectrophotometry, which determined that the wavelength of maximum absorption (λmax) of the organic compounds present in all the water samples was 222 nm. These organic compounds were identified using Gas Chromatography-Mass Spectrometry (GC-MS). The composite water sample obtained from the sachet water revealed sixteen (16) organic compounds, while ten (10) were found in the bottled water composite sample. The common organic compounds found in both the sachet and bottled waters are Neophytadiene, Hexadecanoic acid, Eicosadiene, Cyclotrisiloxane, and Tetrasiloxane. Other organic compounds found only in the composite bottled water samples are: Dodecanoic acid, Octadecadienoic acid, Octadecenoic, Methyl stearate, Benzisothiazol-3-amine, and Arsenous acid. The presence of Arsenous acid is quite worrisome, especially when found in bottled water that most elites in the society drinks. In the composite sachet water sample, other organic compounds found include Copaene, Cubebene, Caryophyllene, Humulene, Naphthalene, Caryophyllene oxide, Tetradecyne, Caffeine, Methyl Hexadecenoic acid, Hexadec-9-enoate, p-Camhorene, Octadecatrienenoic acid, Supraene, and HexamethylCyclotrisiloxane. In general, most of these organic compounds have plant origin but their presence in potable water is undesirable and therefore regarded as contaminants and harmful. The water producing plants need to incorporate effective organic purification systems to remove these organic compounds, which are harmful contaminants from the drinking waters.

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Zhang, Weiqi, Wenqin Wu, Chong Cai, Xiaofeng Hu, Hui Li, Yizhen Bai, Zhaowei Zhang, and Peiwu Li. "A Sensitive, Point-of-Care Detection of Small Molecules Based on a Portable Barometer: Aflatoxins In Agricultural Products." Toxins 12, no. 3 (March 3, 2020): 158. http://dx.doi.org/10.3390/toxins12030158.

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Sensitive and point-of-care detection of small toxic molecules plays a key role in food safety. Aflatoxin, a typical small toxic molecule, can cause serious healthcare and economic issues, thereby promoting the development of sensitive and point-of-care detection. Although ELISA is one of the official detection methods, it cannot fill the gap between sensitivity and point-of-care application because it requires a large-scale microplate reader. To employ portable readers in food safety, Pt-catalysis has attracted increasing attention due to its portability and reliability. In this study, we developed a sensitive point-of-care aflatoxin detection (POCAD) method via a portable handheld barometer. We synthesized and characterized Au@PtNPs and Au@PtNPs conjugated with a second antibody (Au@PtNPs-IgG). A competitive immunoassay was established based on the homemade monoclonal antibody against aflatoxins. Au@PtNPs-IgG was used to catalyze the production of O2 from H2O2 in a sealed vessel. The pressure of O2 was then recorded by a handheld barometer. The aflatoxin concentration was inversely proportional to the pressure recorded via the barometer reading. After optimization, a limit of detection of 0.03 ng/mL and a linear range from 0.09 to 16.0 ng/mL were achieved. Recovery was recorded as 83.1%–112.0% along with satisfactory results regarding inner- and inter-assay precision (relative standard deviation, RSD < 6.4%). Little cross-reaction was observed. Additionally, the POCAD was validated by high-performance liquid chromatography (HPLC) by using peanut and corn samples. The portable POCAD exhibits strong potential for applications in the on-site detection of small toxic molecules to ensure food safety.

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Abonamah, Jocelyn V., Brian A. Eckenrode, and Mehdi Moini. "On-site detection of fentanyl and its derivatives by field portable nano-liquid chromatography-electron lonization-mass spectrometry (nLC-EI-MS)." Forensic Chemistry 16 (December 2019): 100180. http://dx.doi.org/10.1016/j.forc.2019.100180.

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Xu, Dehui, Xinying Zhang, Jin Zhang, Rui Feng, Shuai Wang, and Yanjie Yang. "Metabolomics of Pseudomonas aeruginosa Treated by Atmospheric-Pressure Cold Plasma." Applied Sciences 11, no. 22 (November 9, 2021): 10527. http://dx.doi.org/10.3390/app112210527.

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With increasing drug resistance of Pseudomonas aeruginosa, a new sterilization method is needed. Plasma has been shown to be an effective method of sterilization, but no researchers have studied the effect of plasma on bacterial metabolism. In this paper, we studied the emission spectrum, liquid phase active particles, and other physical and chemical properties of a portable plasma device. Pseudomonas aeruginosa were then treated with activated water generated by surface plasma discharge. Using gas chromatography time-of-flight mass spectrometry (GC-TOF-MS) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis, we obtained the differential metabolite pathways. The results showed that, after plasma activated water treatment, the carbohydrate metabolism of the bacteria was inhibited and the metabolic processes of protein and amino acid decomposition were enhanced. Therefore, water activated by atmospheric-pressure cold plasma can significantly change bacterial metabolites, thus promoting bacterial death.

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Rohner, Fabian, Simone K. Frey, Ralf Mothes, Andrea Hurtienne, Simone Hartong, Patrice Emery Bosso, Mai Bui, Florian J. Schweigert, and Christine Northrop-Clewes. "Quantification of Vitamin A in Palm Oil Using a Fast and Simple Portable Device: Method Validation and Comparison to High-Performance Liquid Chromatography." International Journal for Vitamin and Nutrition Research 81, no. 5 (September 1, 2011): 335–42. http://dx.doi.org/10.1024/0300-9831/a000081.

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Vitamin A deficiency continues to be a global public health problem. Fortification of oil with vitamin A is considered a cost-effective, feasible strategy to prevent this problem but quality control poses a challenge to program implementation. To overcome this, we have validated a newly developed device that quantitatively measures the content of retinyl palmitate in refined palm oil, is simple to use, and yields immediate results.Linearity of analysis ranged from 2.5 - 30 mg retinol equivalents (RE)/ kg of palm oil, with 2.5 mg RE/kg being the determination limit; inter- and intra-assay precision ranged from 1.4 - 7.1 %. Comparison with a high-performance liquid chromatography method showed high agreement between the methods (R2 = 0.92; Limits of Agreement: -1.24 mg to 2.53 mg RE/kg), and further comparisons illustrate that the new device is useful in low-resource settings. This device offers a field- and user-friendly solution to quantifying the vitamin A content in refined palm oil.

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Renaud, Cécile, Jacques Berger, Arnaud Laillou, and Sylvie Avallone. "Quantification of Vitamin A in Fortified Rapeseed, Groundnut and Soya Oils Using a Simple Portable Device: Comparison to High Performance Liquid Chromatography." International Journal for Vitamin and Nutrition Research 83, no. 2 (April 1, 2013): 122–28. http://dx.doi.org/10.1024/0300-9831/a000154.

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Vitamin A deficiency is still one of the major public health problems in least developed countries. Fortification of vegetable oils is a strategy implemented worldwide to prevent this deficiency. For a fortification program to be effective, regular monitoring is necessary to control food quality in the producing units. The reference methods for vitamin A quantification are expensive and time-consuming. A rapid method should be useful for regular assessment of vitamin A in the oil industry. A portable device was compared to high-performance liquid chromatography (HPLC) for three plant oils (rapeseed, groundnut, and soya). The device presented a good linearity from 3 to 30 mg retinol equivalents per kg (mg RE.kg- 1). Its limits of detection and quantification were 3 mg RE.kg- 1 for groundnut and rapeseed oils and 4 mg RE.kg- 1 for soya oil. The intra-assay precision ranged from 1.48 % to 3.98 %, considered satisfactory. Accuracy estimated by the root mean squares error ranged from 3.99 to 5.49 and revealed a lower precision than HPLC (0.4 to 2.25). Although it offers less precision than HPLC, the device estimates quickly the vitamin A content of the tested oils from 3 or 4 to 15 mg RE.kg- 1.

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PENG, TAO, FU S. ZHANG, WAN C. YANG, DONG X. LI, YUAN CHEN, YONG H. XIONG, HUA WEI, and WEI H. LAI. "Lateral-Flow Assay for Rapid Quantitative Detection of Clorprenaline Residue in Swine Urine." Journal of Food Protection 77, no. 10 (October 1, 2014): 1824–29. http://dx.doi.org/10.4315/0362-028x.jfp-14-103.

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Clorprenaline (CLP), a β2-adrenergic agonist, was first found in veterinary drugs for cold treatment in China in 2013. It is a potential new lean meat-boosting feed additive because it can promote animal muscular mass growth and decrease fat accumulation. A competitive colloidal gold-based lateral flow immunoassay system with a portable strip reader was successfully developed for rapid quantitative detection of CLP residue in swine urine. The detection system was optimized so that the detection can be completed within 9 min with a limit of detection of 0.15 μg·liter−1. The assay exhibited good linear range from 3.0 to 20.0 μg·liter−1, with reliable correlation of 0.9970 and with no obvious cross-reaction with five other β2-agonist compounds. Twenty spiked swine urine samples were tested by lateral flow immunoassay and liquid chromatography–tandem mass spectrometry to confirm the accuracy of the system. Results show good correlation between the two methods. This method is rapid, sensitive, specific, and convenient. It can be applied in the field for on-site detection of CLP in urine samples.

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Pérez-Fernández, Beatriz, Agustín Costa-García, and Alfredo de la Escosura Muñiz. "Electrochemical (Bio)Sensors for Pesticides Detection Using Screen-Printed Electrodes." Biosensors 10, no. 4 (April 2, 2020): 32. http://dx.doi.org/10.3390/bios10040032.

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Pesticides are among the most important contaminants in food, leading to important global health problems. While conventional techniques such as high-performance liquid chromatography (HPLC) and mass spectrometry (MS) have traditionally been utilized for the detection of such food contaminants, they are relatively expensive, time-consuming and labor intensive, limiting their use for point-of-care (POC) applications. Electrochemical (bio)sensors are emerging devices meeting such expectations, since they represent reliable, simple, cheap, portable, selective and easy to use analytical tools that can be used outside the laboratories by non-specialized personnel. Screen-printed electrodes (SPEs) stand out from the variety of transducers used in electrochemical (bio)sensing because of their small size, high integration, low cost and ability to measure in few microliters of sample. In this context, in this review article, we summarize and discuss about the use of SPEs as analytical tools in the development of (bio)sensors for pesticides of interest for food control. Finally, aspects related to the analytical performance of the developed (bio)sensors together with prospects for future improvements are discussed.

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Huml, Lukáš, Jan Tauchen, Silvie Rimpelová, Barbora Holubová, Oldřich Lapčík, and Michal Jurášek. "Advances in the Determination of Anabolic-Androgenic Steroids: From Standard Practices to Tailor-Designed Multidisciplinary Approaches." Sensors 22, no. 1 (December 21, 2021): 4. http://dx.doi.org/10.3390/s22010004.

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Anabolic-androgenic steroids (AASs), a group of compounds frequently misused by athletes and, unfortunately, also by the general population, have lately attracted global attention; thus, significant demands for more precise, facile, and rapid AAS detection have arisen. The standard methods ordinarily used for AAS determination include liquid and gas chromatography coupled with mass spectrometry. However, good knowledge of steroid metabolism, pretreatment of samples (such as derivatization), and well-trained operators of the instruments are required, making this procedure expensive, complicated, and not routinely applicable. In the drive to meet current AAS detection demands, the scientific focus has shifted to developing novel, tailor-made approaches leading to time- and cost-effective, routine, and field-portable methods for AAS determination in various matrices, such as biological fluids, food supplements, meat, water, or other environmental components. Therefore, herein, we present a comprehensive review article covering recent advances in AAS determination, with a strong emphasis on the increasingly important role of chemically designed artificial sensors, biosensors, and antibody- and fluorescence-based methods.

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Alves Filho, Silva, Lima, Ribeiro, Silva, Zocolo, Canuto, Morais, Castro, and de Brito. "Metabolomic Variability of Different Genotypes of Cashew by LC-Ms and Correlation with Near-Infrared Spectroscopy as a Tool for Fast Phenotyping." Metabolites 9, no. 6 (June 25, 2019): 121. http://dx.doi.org/10.3390/metabo9060121.

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The objective of the present work was to develop an advanced fast phenotyping tool to explore the cashew apple compositions from different genotypes, based on a portable near-infrared (MicroNIR) spectroscopy. This will be in addition to associating the variability of the respective cashew apple pulps with the genotypes by ultra-performance liquid chromatography (UPLC), coupled with high-resolution mass spectrometry (HRMS). The NIR analysis is a non-destructive, low-cost procedure that provides prompt results, while considering the morphology of different cashew apples (shape, size, and color). The UPLC-HRMS analysis is characterized by specific bioactive compounds, such as the derivatives of hydroxybutanoic acid, galloyl, and flavonoids. Furthermore, both techniques allowed the identification of a group of accessions, which presented similarities among the chemical profiling. However, to improve the understanding of cashew chemical and physical variability, further variables related to the cashew apple composition, such as edaphoclimatic conditions, should be considered for future studies. These approaches lead to the conclusion that these two tools are useful for the maintenance of BAG-Caju (Cashew Germplasm Bank) and for the cashew-breeding program.

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Krämer, Irene, and Judith Thiesen. "Stability of topotecan infusion solutions in polyvinylchloride bags and elastomeric portable infusion devices." Journal of Oncology Pharmacy Practice 5, no. 2 (June 1999): 75–82. http://dx.doi.org/10.1177/107815529900500203.

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Purpose. The purpose of this study was to determine the physicochemical stability of topotecan after reconstitution and after further dilution in two commonly used infusion fluids (0.9% sodium chloride, 5% dextrose) in both polyvinylchloride (PVC) bags and elastomeric portable infusion devices. Methods. Each vial of topotecan (Hycamtin®) was reconstituted with sterile water for injection, yielding a nominal concentration of 1 mg/mL. Topotecan infusion solutions were aseptically prepared by further dilution of reconstituted topotecan solutions with either 0.9% sodium chloride or 5% dextrose in both PVC bags and portable elastomeric infusion devices, in amounts yielding topotecan concentrations of 10 µg/mL, 25 µg/mL, or 50 µg/mL. Test solutions were stored light-protected at room temperature (25°C) or under refrigeration (2-8°C) in parallel. One test solution of the nominal concentration of 10 µg/mL topotecan in a 0.9% sodium chloride PVC infusion bag was stored under ambient light conditions (mixed daylight and normal laboratory fluorescent light) at room temperature. Topotecan concentrations were obtained periodically throughout a 4-week storage period via a stability-indicating high performance liquid chromatography assay with ultra-violet detection. In addition, measurements of pH values were performed regularly, and test solutions were visually examined for colour change and precipitation. Results. The stability tests revealed that the currently available topotecan formulation is stable (at a level of ≥90% topotecan) after reconstitution and dilution, independent of temperature (refrigerated, room temperature), the vehicle (0.9% sodium chlo-ride, 5% dextrose), the concentration (10 µg/mL, 25 µg/mL, or 50 µg/mL), or the container material (PVC bags, elastomeric portable infusion devices). The results were obtained over a test period of ≥4 weeks. Topotecan infusion solutions exposed to daylight were stable for only 17 days. Conclusions. Reconstituted and diluted topotecan infusion solutions are shown to be physicochemically stable for 4 weeks. Light protection during administration is not necessary.

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Yu, Jie, Zhichao Zhang, Quanfang Lu, Duixiong Sun, Shuwen Zhu, Xiaomin Zhang, Xing Wang, and Wu Yang. "High-Sensitivity Determination of K, Ca, Na, and Mg in Salt Mines Samples by Atomic Emission Spectrometry with a Miniaturized Liquid Cathode Glow Discharge." Journal of Analytical Methods in Chemistry 2017 (2017): 1–10. http://dx.doi.org/10.1155/2017/7105831.

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An atomic emission spectrometer (AES) based on a novel atmospheric pressure liquid cathode glow discharge (LCGD) as one of the most promising miniaturized excitation sources has been developed, in which the glow discharge is produced between a needle-like Pt anode and the electrolyte (as cathode) overflowing from a quartz capillary. Lower energy consumption (<50 W) and higher excitation efficiency can be realized by point discharge of the needle-like Pt. The miniaturized LCGD seems particularly well suited to rapid and high-sensitivity determination of K, Ca, Na, and Mg in salt mines samples. The optimized analytical conditions of LCGD-AES were pH = 1 with HNO3 as electrolyte, 650 V discharge voltage, and 3 mL min−1 solution flow rate. The limits of detections (LODs) of K, Ca, Na, and Mg were 0.390, 0.054, 0.048, and 0.032 mg L−1, respectively. Measurement results of the LCGD-AES are in good agreement with the comparison value obtained by inductively coupled plasma (ICP) and ion chromatography (IC). All results suggested that the developed portable analytical instrument can be used for on-site and real-time monitoring of metal elements in field with further improvement.

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May, Marisa C., David C. Pavone, and Ira S. Lurie. "The separation and identification of synthetic cathinones by portable low microflow liquid chromatography with dual capillary columns in series and dual wavelength ultraviolet detection." Journal of Separation Science 43, no. 19 (August 19, 2020): 3756–64. http://dx.doi.org/10.1002/jssc.202000767.

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Zhang, Boxin, Xingwei Hou, Cheng Zhen, and Alan X. Wang. "Sub-Part-Per-Billion Level Sensing of Fentanyl Residues from Wastewater Using Portable Surface-Enhanced Raman Scattering Sensing." Biosensors 11, no. 10 (October 3, 2021): 370. http://dx.doi.org/10.3390/bios11100370.

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Detection of illicit drug residues from wastewater provides a new route toward community-level assessment of drug abuse that is critical to public health. However, traditional chemistry analytical tools such as high-performance liquid chromatography in tandem with mass spectrometry (HPLC-MS) cannot meet the large-scale testing requirement in terms of cost, promptness, and convenience of use. In this article, we demonstrated ultra-sensitive and portable surface-enhanced Raman scattering sensing (SERS) of fentanyl, a synthetic opioid, from sewage water and achieved quantitative analysis through principal component analysis and partial least-squares regression. The SERS substrates adopted in this application were synthesized by in situ growth of silver nanoparticles on diatomaceous earth films, which show ultra-high sensitivity down to 10 parts per trillion in artificially contaminated tap water in the lab using a commercial portable Raman spectrometer. Based on training data from artificially contaminated tap water, we predicted the fentanyl concentration in the sewage water from a wastewater treatment plant to be 0.8 parts per billion (ppb). As a comparison, the HPLC-MS confirmed the fentanyl concentration was below 1 ppb but failed to provide a specific value of the concentration since the concentration was too low. In addition, we further proved the validity of our SERS sensing technique by comparing SERS results from multiple sewage water treatment plants, and the results are consistent with the public health data from our local health authority. Such SERS sensing technique with ultra-high sensitivity down to sub-ppb level proved its feasibility for point-of-care detection of illicit drugs from sewage water, which is crucial to assess public health.

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De Jesus Inacio, Luciana, Ilaria Lanza, Roberta Merlanti, Barbara Contiero, Lorena Lucatello, Lorenzo Serva, Vittoria Bisutti, et al. "Discriminant analysis of pyrrolizidine alkaloid contamination in bee pollen based on near-infrared data from lab-stationary and portable spectrometers." European Food Research and Technology 246, no. 12 (August 29, 2020): 2471–83. http://dx.doi.org/10.1007/s00217-020-03590-0.

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AbstractBee pollen may be contaminated with pyrrolizidine alkaloids (PAs) and their N-oxides (PANOs), which are mainly detected by liquid chromatography coupled to tandem mass spectrometry (LC–MS/MS), even though the use of fast near-infrared (NIR) spectroscopy is an ongoing alternative. Therefore, the main challenge of this study was to assess the feasibility of both a lab-stationary (Foss) and a portable (Polispec) NIR spectrometer in 60 dehydrated bee pollen samples. After an ANOVA-feature selection of the most informative NIR spectral data, canonical discriminant analysis (CDA) was performed to distinguish three quantitative PA/PANO classes (µg/kg): < LOQ (0.4), low; 0.4–400, moderate; > 400, high. According to the LC–MS/MS analysis, 77% of the samples were contaminated with PAs/PANOs and the sum content of the 17 target analytes was higher than 400 µg/kg in 28% of the samples. CDA was carried out on a pool of 18 (Foss) and 22 (Polispec) selected spectral variables and allowed accurate classification of samples from the low class as confirmed by the high values of Matthews correlation coefficient (≥ 0.91) for both NIR spectrometers. Leave-one-out cross-validation highlighted precise recognition of samples characterised by a high PA/PANO content with a low misclassification rate (0.02) as false negatives. The most informative wavelengths were within the < 1000, 1000–1660 and > 2400 nm regions for Foss and > 1500 nm for Polispec that could be associated with cyclic amines, and epoxide chemical structures of PAs/PANOs. In sum, both lab-stationary and portable NIR systems are reliable and fast techniques for detecting PA/PANO contamination in bee pollen.

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Wang, Wei, Jingneng Wang, Min Wang, and Juan Shen. "Rapid Quantification of Chlorpromazine Residues in Pork Using Nanosphere-Based Time-Resolved Fluorescence Immunoassay Analyzer." International Journal of Analytical Chemistry 2021 (March 9, 2021): 1–8. http://dx.doi.org/10.1155/2021/6633016.

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Immunochromatographic assays are good analytical tools for the detection of drug residues. We report a nanosphere-based time-resolved fluorescence immunoassay (nano-TRFIA) based on a monoclonal antibody and a portable TRFIA analyzer for the rapid quantification of chlorpromazine (CPZ) residues in pork. Under optimal conditions, the nano-TRFIA detected CPZ residues within 6 min of sample pretreatment. The results showed good linearity (R2 = 0.991), with a limit of detection (LOD) of 0.32 μg/kg, a wide dynamic range of 0.46–10.0 μg/kg, and coefficients of variation (CVs) of the overall intrabatch and interbatch assays of 7.34% and 7.65%, respectively. The nano-TRFIA was also used to detect CPZ at different spiked concentrations in pork, and the results were confirmed via ultraperformance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The nano-TRFIA was evaluated for the analysis of six commercial pork samples, and the results agreed well with those obtained via UPLC-MS/MS, without significant differences ( P > 0.05 ). Therefore, the proposed nano-TRFIA is a powerful alternative for the rapid and accurate quantification of CPZ residues in pork to meet the required Chinese maximum residue limits for veterinary drugs in foods.

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Wu, Yuping, Jia Wang, Yong Zhou, Yonghua Qi, Licai Ma, Xuannian Wang, and Xiaoqi Tao. "Quantitative Determination of Nitrofurazone Metabolites in Animal-Derived Foods Based on a Background Fluorescence Quenching Immunochromatographic Assay." Foods 10, no. 7 (July 20, 2021): 1668. http://dx.doi.org/10.3390/foods10071668.

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Due to their facile synthesis and friendly functionalization, gold nanoparticles (AuNPs) have been applied in all kinds of biosensors. More importantly, these biosensors, with the combination of AuNPs and immunoassay, are expected to be used for the detection of different compounds with low concentrations in complex samples. In this study, a AuNPs-labeled antibody immunoprobe was prepared and combined with a fluorescence-quenching principle and a background fluorescence-quenching immunochromatographic assay (bFQICA), achieving rapid on-site detection. By using a portable fluorescence immunoquantitative analyzer and a QR code with a built-in standard curve, the rapid quantitative determination for nitrofurazone metabolite of semicarbazide (SEM) in animal-derived foods was realized. The limits of detection (LODs) for bFQICA in egg, chicken, fish, and shrimp were 0.09, 0.10, 0.12, and 0.15 μg kg−1 for SEM, respectively, with the linear range of 0.08–0.41 μg L−1, the recoveries ranging from 73.5% to 109.2%, and the coefficient of variation <15%, only taking 13 min for the SEM detection. The analysis of animal-derived foods by bFQICA complied with that of liquid chromatography-tandem mass spectrometry (LC-MS/MS).

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Jardine, K. J., W. M. Henderson, T. E. Huxman, and L. Abrell. "Dynamic Solution Injection: a new method for preparing pptv–ppbv standard atmospheres of volatile organic compounds." Atmospheric Measurement Techniques 3, no. 6 (November 16, 2010): 1569–76. http://dx.doi.org/10.5194/amt-3-1569-2010.

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Abstract. Proton Transfer Reaction-Mass Spectrometry (PTR-MS) and thermal desorption Gas Chromatography-Mass Spectrometry (GC-MS) allow for absolute quantification of a wide range of atmospheric volatile organic compounds (VOCs) with concentrations in the ppbv to pptv range. Although often neglected, routine calibration is necessary for accurate quantification of VOCs by PTR-MS and GC-MS. Several gas calibration methods currently exist, including compressed gas cylinders, permeation tubes, diffusion tubes, and liquid injection. While each method has its advantages and limitations, no single technique has emerged that is capable of dynamically generating known concentrations of complex mixtures of VOCs over a large concentration range (ppbv to pptv) and is technically simple, field portable, and affordable. We present the development of a new VOC calibration technique based on liquid injection with these features termed Dynamic Solution Injection (DSI). This method consists of injecting VOCs (0.1–0.5 mM) dissolved in cyclohexane (PTR-MS) or methanol (GC-MS) into a 1.0 slpm flow of purified dilution gas in an unheated 25 ml glass vial. Upon changes in the injection flow rate (0.5–4.0 μl min−1), new VOC concentrations are reached within seconds to minutes, depending on the compound, with a liquid injection flow rate accuracy and precision of better than 7% and 4% respectively. We demonstrate the utility of the DSI technique by calibrating a PTR-MS to seven different cyclohexane solutions containing a total of 34 different biogenic compounds including volatile isoprenoids, oxygenated VOCs, fatty acid oxidation products, aromatics, and dimethyl sulfide. We conclude that because of its small size, low cost, and simplicity, the Dynamic Solution Injection method will be of great use to both laboratory and field VOC studies.

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Ito, H., H. Horie, Y. Nagai, K. Ippoushi, and K. Azuma. "THE DETERMINATION OF NITRATE IN SPINACH AND JAPANESE RADISHES BY RQFLEX, PORTABLE ION ELECTRODE (PIE), HIGH PERFORMANCE LIQUID CHROMATOGRAPHY (HPLC) AND HIGH PERFORMANCE CAPILLARY ELECTROPHORESIS (CE)." Acta Horticulturae, no. 604 (July 2003): 545–48. http://dx.doi.org/10.17660/actahortic.2003.604.63.

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Bourget, Philippe, Alexandre Amin, Fabrice Vidal, Christophe Merlette, and Frédéric Lagarce. "Comparison of Raman spectroscopy vs. high performance liquid chromatography for quality control of complex therapeutic objects: Model of elastomeric portable pumps filled with a fluorouracil solution." Journal of Pharmaceutical and Biomedical Analysis 91 (March 2014): 176–84. http://dx.doi.org/10.1016/j.jpba.2013.12.030.

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Калинин, А. В., В. Н. Крашенинников, and В. Н. Титов. "Изучение корреляций содержания клинически важных жирных кислот в пище и крови со спектрами поглощения ближнего инфракрасного диапазона." Журнал технической физики 127, no. 7 (2019): 137. http://dx.doi.org/10.21883/os.2019.07.47940.103-19.

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AbstractFatty acid triglycerides are essential components of the human diet, while possessing unique biological activity. Their content in biological media is traditionally determined by gas and liquid chromatography. They are not readily available for mass analysis of food products and blood serum due to the complexity of these methods. The aim of our work is to study the correlation of the absorption spectra of near-infrared radiation with the characteristic oscillations of functional groups of clinically important fatty acids, such as palmitic saturated ones and oleic and linoleic unsaturated ones, as well as their trans -isomers, as well as to develop techniques and test equipment for rapid assessment of their content in fat products and blood serum. As a result, evidence of the applicability of the Fourier spectrometer in the wavelength range of 1.0–2.4 μm for the operational analysis of clinically important fatty acids in butter, spreads and serum, as well as the correlation of the absorption spectra of serum with the content of total triglycerides and cholesterol were revealed. In addition, using a portable spectrometer in the wavelength range of 1.0–1.65 μm suitable for mass analysis of fat-and-oil products quality, the content of these fatty acids was determined, and the selectivity of their determination was studied.

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Shemesh, T., LS Piers, and K. O'Dea. "Use of the Bayer DCA 2000+ for the measurement of glycated haemoglobin in a remote Australian Aboriginal community." Annals of Clinical Biochemistry: International Journal of Laboratory Medicine 40, no. 5 (September 1, 2003): 566–68. http://dx.doi.org/10.1258/000456303322326515.

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Background: Good glycaemic control in type 2 diabetes can reduce both morbidity and mortality, and monitoring of glycated haemoglobin A1c (HbA1c) is currently recommended for this purpose. Methods: Haemoglobin A1c can be measured using the portable Bayer DCA 2000+. As part of a community-based screening project for chronic diseases, subjects with impaired fasting glucose concentrations or diabetes had their HbA1c concentration measured on the analyser. HbA1c measurements were also made in a laboratory using cation-exchange high-performance liquid chromatography. Results were then compared to those obtained in the field. HbA1c values were loge transformed to obtain a normal distribution. Results: Mean (95% confidence interval) HbA1c measured on the DCA 2000+ ( n = 39) was 6.3% (5.8, 6.9%), while that measured in the laboratory was 6.5% (6.0, 7.0%). The correlation coefficient ( r) between the measurements was 0.96 ( P < 0.01). Bland-Altman analysis revealed that the DCA 2000+ estimate of HbA1c could be used interchangeably with that from the laboratory (mean bias = 0.1%, limits of agreement - 1.1, 0.8%). The sensitivity, specificity and positive predictive value of the DCA 2000+ estimate of HbA1c using a cut-off value of <7% for adequate glycaemic control, were all 100%. Conclusions: The DCA 2000+ may be used to measure HbA1c in remote communities.

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Masilamani, Vadivel, Sandanasamy Devanesan, Fatma AlQathani, Mashael AlShebly, Hebatullah Hassan Daban, Duran Canatan, Karim Farhat, Mansour Jabry, and Mohamad S. AlSalhi. "A Novel Technique of Spectral Discrimination of Variants of Sickle Cell Anemia." Disease Markers 2018 (August 27, 2018): 1–7. http://dx.doi.org/10.1155/2018/5942368.

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Sickle cell anemia (SCA) is an inherited blood disorder with worldwide incidence of 15%; out of this, it is found in up to 20% in countries like Kingdom of Saudi Arabia and Bahrain. The standard conventional method of detection is complete blood count (CBC) followed by hemoglobin electrophoresis or high-performance liquid chromatography (HPLC) or both. In this context, spectral detection of variants of sickle cell anemia (SCA) is an innovative technique, which when made accurate and reliable could be an effective alternative, since the instrumentation is compact (5 kg) and hence portable. This makes mass screening even in remote villages possible. In this paper, we give the essential aspects of fluorescent spectral features of sickle cell trait (SCT), sickle cell disease (SCD), beta (β) thalassemia trait (BTT) + SCD, and beta (β) thalassemia disease (BTD) + SCD. All the above four major variants could be discriminated among themselves and also from the normal control blood sample. All these analyses could be carried out with 5 ml of blood, in a time period of 10 minutes. The results of this paper give strong support for an alternative method, a spectral technique, for molecular-level diagnosis of sickle cell anemia and other closely related blood disorders.

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Luo, Hongzhi, Shan Liu, Lina Shi, Zhu Li, Qianwen Bai, Xiaoxin Du, Lijun Wang, He Zha, and Chenzhong Li. "Paper-Based Fluidic Sensing Platforms for β-Adrenergic Agonist Residue Point-of-Care Testing." Biosensors 12, no. 7 (July 12, 2022): 518. http://dx.doi.org/10.3390/bios12070518.

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The illegal use of β-adrenergic agonists during livestock growth poses a threat to public health; the long-term intake of this medication can cause serious physiological side effects and even death. Therefore, rapid detection methods for β-adrenergic agonist residues on-site are required. Traditional detection methods such as liquid chromatography have limitations in terms of expensive instruments and complex operations. In contrast, paper methods are low cost, ubiquitous, and portable, which has led to them becoming the preferred detection method in recent years. Various paper-based fluidic devices have been developed to detect β-adrenergic agonist residues, including lateral flow immunoassays (LFAs) and microfluidic paper-based analytical devices (μPADs). In this review, the application of LFAs for the detection of β-agonists is summarized comprehensively, focusing on the latest advances in novel labeling and detection strategies. The use of μPADs as an analytical platform has attracted interest over the past decade due to their unique advantages and application for detecting β-adrenergic agonists, which are introduced here. Vertical flow immunoassays are also discussed for their shorter assay time and stronger multiplexing capabilities compared with LFAs. Furthermore, the development direction and prospects for the commercialization of paper-based devices are considered, shedding light on the development of point-of-care testing devices for β-adrenergic agonist residue detection.

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López-Pastor, Jose-Antonio, Ascensión Martínez-Sánchez, Juan Aznar-Poveda, Antonio-Javier García-Sánchez, Joan García-Haro, and Encarnación Aguayo. "Quick and Cost-Effective Estimation of Vitamin C in Multifruit Juices Using Voltammetric Methods." Sensors 20, no. 3 (January 26, 2020): 676. http://dx.doi.org/10.3390/s20030676.

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Ascorbic Acid (AA) is a natural and powerful water-soluble antioxidant associated with long-lasting food products. As time passes, the AA content in products sharply decreases, and they become increasingly degraded. There are several techniques to precisely quantify AA concentrations. However, most of them employ costly laboratory instruments, such as High-Performance Liquid Chromatography (HPLC) or complex electrochemical methods, which make unfeasible recurrent AA measurements along the entire supply chain. To address this issue, we contribute with an in-field and real-time voltammetric method, carried out with a low-cost, easy-to-use, and portable device. An unmodified Screen-Printed Electrode (SPE) is used together with the device to achieve short reading times. Our method has been extensively tested in two multifruit juices using three different SPEs. Calibration curves and Limit of Detection were derived for each SPE. Furthermore, periodic experiments were conducted to study the shelf life of juices under consideration. During the analysis, a set of assays for each SPE were implemented to determine the remaining AA amount per juice and compare it with that obtained using HPLC under the same conditions. Results revealed that our cost-effective device is fully comparable to the HPLC equipment, as long as the juice does not include certain interferents; a scenario also contemplated in this article.

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Koch, Cosima, Andreas E. Posch, Christoph Herwig, and Bernhard Lendl. "Comparison of Fiber Optic and Conduit Attenuated Total Reflection (ATR) Fourier Transform Infrared (FT-IR) Setup for In-Line Fermentation Monitoring." Applied Spectroscopy 70, no. 12 (November 19, 2016): 1965–73. http://dx.doi.org/10.1177/0003702816662618.

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Abstract:

The performance of a fiber optic and an optical conduit in-line attenuated total reflection mid-infrared (IR) probe during in situ monitoring of Penicillium chrysogenum fermentation were compared. The fiber optic probe was connected to a sealed, portable, Fourier transform infrared (FT-IR) process spectrometer via a plug-and-play interface. The optical conduit, on the other hand, was connected to a FT-IR process spectrometer via a knuckled probe with mirrors that had to be adjusted prior to each fermentation, which were purged with dry air. Penicillin V (PenV) and its precursor phenoxyacetic acid (POX) concentrations were determined by online high-performance liquid chromatography and the obtained concentrations were used as reference to build partial least squares regression models. Cross-validated root-mean-square errors of prediction were found to be 0.2 g L−1 (POX) and 0.19 g L−1 (PenV) for the fiber optic setup and 0.17 g L−1 (both POX and PenV) for the conduit setup. Higher noise-levels and spectrum-to-spectrum variations of the fiber optic setup lead to higher noise of estimated (i.e., unknown) POX and PenV concentrations than was found for the conduit setup. It seems that trade-off has to be made between ease of handling (fiber optic setup) and measurement accuracy (optical conduit setup) when choosing one of these systems for bioprocess monitoring.

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Journal articles on the topic 'Portable liquid chromatography'

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