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Analytical chemistry

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https://www.readbyqxmd.com/read/28651108/synchronous-characterization-of-carbohydrates-and-ginsenosides-yields-deeper-insights-into-the-processing-chemistry-of-ginseng
#1
Shan-Shan Zhou, Jun Xu, Ming Kong, Ka-Man Yip, Jin-Di Xu, Hong Shen, Zhong-Zhen Zhao, Song-Lin Li, Hu-Biao Chen
Carbohydrates and ginsenosides in ginseng are biologically interrelated. Their synchronous analysis is therefore essential in chemical research on ginseng to characterize its "holistic" quality. Here we investigated the processing chemistry of red ginseng (RG), a ginseng product processed by water-steaming, for which both carbohydrates and ginsenosides were qualitatively and quantitatively determined through multiple analytical techniques. Results revealed that the steam-processing not only qualitatively and quantitatively altered the ginsenosides but also affected the polymeric carbohydrates via changing their physiochemical parameters, i...
June 19, 2017: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/28647912/chemiluminescent-immunoassay-technology-what-does-it-change-in-autoantibody-detection
#2
Luigi Cinquanta, Desré Ethel Fontana, Nicola Bizzaro
Diagnostic technology is rapidly evolving, and over the last decade, substantial progress has been made even for the identification of antibodies, increasingly approaching this type of diagnostic to that of automated clinical chemistry laboratory. In this review, we describe the analytical and diagnostic characteristics of chemiluminescence technology in its strength and in its applicability for a more rapid and accurate diagnosis of autoimmune diseases. The wide dynamic range, greater than that of immunoenzymatic methods, the high sensitivity and specificity of the results expressed in quantitative form, the high degree of automation and the clinical implications related to the reduction in the turnaround time, and the ability to run a large number of antibody tests (even of different isotypes), directed towards large antigenic panels in random access mode, make this technology the most advanced in the clinical laboratory, with enormous repercussions on the workflow and on the autoimmunology laboratory organisation...
December 2017: Auto- Immunity Highlights
https://www.readbyqxmd.com/read/28647526/national-survey-of-adult-and-pediatric-reference-intervals-in-clinical-laboratories-across-canada-a-report-of-the-cscc-working-group-on-reference-interval-harmonization
#3
Khosrow Adeli, Victoria Higgins, David Seccombe, Christine P Collier, Cynthia Balion, George Cembrowski, Allison A Venner, Julie Shaw
OBJECTIVE: Reference intervals are widely used decision-making tools in laboratory medicine, serving as health-associated standards to interpret laboratory test results. Numerous studies have shown wide variation in reference intervals, even between laboratories using assays from the same manufacturer. Lack of consistency in either sample measurement or reference intervals across laboratories challenges the expectation of standardized patient care regardless of testing location. Here, we present data from a national survey conducted by the Canadian Society of Clinical Chemistry (CSCC) Reference Interval Harmonization (hRI) Working Group that examines the variation in laboratory reference sample measurements, as well as pediatric and adult reference intervals currently used in clinical practice across Canada...
June 21, 2017: Clinical Biochemistry
https://www.readbyqxmd.com/read/28644760/expression-and-characterization-of-soybean-seed-coat-peroxidase-in-escherichia-coli-bl21-de3
#4
Changqing Liu, Kai Zheng, Ying Xu, Lacmata Tamekou Stephen, Jiming Wang, Hongwei Zhao, Tongqing Yue, Rui Nian, Haibo Zhang, Mo Xian, Huizhou Liu
Soybean seed coat peroxidase(SBP) is a valuable enzyme having a broad variety of applications in analytical chemistry, biochemistry and food processing. In the present study, the sscp gene (Gene ID: 548068) was optimized based on the preferred codon usage of Escherichia coli, synthesized, and expressed in E. coli BL21(DE3). SDS-PAGE and western blot analysis of this expressed protein revealed that its molecular weight is approximately 39 kDa. The effects of induction temperature, concentration of IPTG (isopropyl-β-D-thiogalactoside) and hemin, induction time, expression time were optimized to enhance SBP production with a maximum activity of 11...
June 23, 2017: Preparative Biochemistry & Biotechnology
https://www.readbyqxmd.com/read/28643351/quality-specifications-of-routine-clinical-chemistry-methods-based-on-sigma-metrics-in-performance-evaluation
#5
Jun Xia, Su-Feng Chen, Fei Xu, Yong-Lie Zhou
INTRODUCTION: Sigma metrics were applied to evaluate the performance of 20 routine chemistry assays, and individual quality control criteria were established based on the sigma values of different assays. METHODS: Precisions were expressed as the average coefficient variations (CVs) of long-term two-level chemistry controls. The biases of the 20 assays were obtained from the results of trueness programs organized by National Center for Clinical Laboratories (NCCL, China) in 2016...
June 23, 2017: Journal of Clinical Laboratory Analysis
https://www.readbyqxmd.com/read/28634759/current-applications-of-high-resolution-mass-spectrometry-for-the-analysis-of-new-psychoactive-substances-a-critical-review
#6
REVIEW
Daniel Pasin, Adam Cawley, Sergei Bidny, Shanlin Fu
The proliferation of new psychoactive substances (NPS) in recent years has resulted in the development of numerous analytical methods for the detection and identification of known and unknown NPS derivatives. High-resolution mass spectrometry (HRMS) has been identified as the method of choice for broad screening of NPS in a wide range of analytical contexts because of its ability to measure accurate masses using data-independent acquisition (DIA) techniques. Additionally, it has shown promise for non-targeted screening strategies that have been developed in order to detect and identify novel analogues without the need for certified reference materials (CRMs) or comprehensive mass spectral libraries...
June 20, 2017: Analytical and Bioanalytical Chemistry
https://www.readbyqxmd.com/read/28631236/use-of-ctx-i-and-pinp-as-bone-turnover-markers-national-bone-health-alliance-recommendations-to-standardize-sample-handling-and-patient-preparation-to-reduce-pre-analytical-variability
#7
P Szulc, K Naylor, N R Hoyle, R Eastell, E T Leary
N-terminal propeptide of type I procollagen and C-terminal telopeptide of type I collagen are the reference standards for bone turnover markers for monitoring osteoporosis treatment. We provide recommendations for standardized sample handling and encompassing aspects of preanalytical variability to improve the reproductibility of their measurements, their reliability, and clinical interpretation. The International Osteoporosis Foundation and International Federation of Clinical Chemistry bone turnover marker standards working group have identified N-terminal propeptide of type I procollagen (PINP) and C-terminal telopeptide of type I collagen (CTX-I) in the blood to be the international reference standards for bone turnover markers for the prediction of fracture risk and monitoring of osteoporosis treatment...
June 19, 2017: Osteoporosis International
https://www.readbyqxmd.com/read/28629218/two-dimensional-plasmonic-nanoparticle-as-a-nanoscale-sensor-to-probe-polymer-brush-formation
#8
Assad Ullah Khan, Clayton Scruggs, David Hicks, Guoliang Liu
Conventional analysis and characterization of polymer brush formation relies on laborious methods that use quartz crystal microbalance, atomic force microscope, microcantilever, or other tools that measure concentration change of solutions. Herein we develop a simple and easy method that utilizes intrinsically-flat two-dimensional (2D) plasmonic nanoparticles as sensors for unveiling the mechanism of polymer brush formation on surfaces. Via ultraviolet-visible spectroscopy, the plasmonic nanoparticles can be used to determine the amount of polymers near the surface in situ...
June 20, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/28625144/detection-of-poor-quality-artemisinin-based-combination-therapy-act-medicines-marketed-in-benin-using-simple-and-advanced-analytical-techniques
#9
Achille Yemoa, Védaste Habyalimana, Jérémie K Mbinze, Victoria Crickboom, Benjamin Muhigirwa, Agnès Ngoya, Pierre-Yves Sacré, Fernand Gbaguidi, Joëlle Quetin-Leclercq, Philippe Hubert, Roland D Marini
BACKGROUND: Poor quality antimalarial medicines still represent a threat to the public health, especially in Sub-Saharan Africa who bears a disproportionate share of the global burden of malaria. It is essential and urgent to strengthen mechanisms against counterfeit medicines. One of the approaches is regular market surveillance through quality controls. METHODS: 12 samples of artemether/lumefantrine were collected from formal and informal drug sellers in Cotonou (Benin) as well as additional other similar samples from Rwanda (13 samples) and from D...
June 15, 2017: Current Drug Safety
https://www.readbyqxmd.com/read/28624482/nmr-quantification-of-trimethylamine-n-oxide-in-human-serum-and-plasma-in-the-clinical-laboratory-setting
#10
Erwin Garcia, Justyna Wolak-Dinsmore, Zeneng Wang, Xinmin S Li, Dennis W Bennett, Margery A Connelly, James D Otvos, Stanley L Hazen, Elias J Jeyarajah
BACKGROUND AND OBJECTIVES: Trimethylamine-N-oxide (TMAO) produced by gut microbiota metabolism of dietary choline and carnitine has been shown to be associated with increased risk of cardiovascular disease (CVD) and to provide incremental clinical prognostic utility beyond traditional risk factors for assessing a patient's CVD risk. The aim of this study was to develop an automated nuclear magnetic resonance (NMR) spectroscopy assay for quantification of TMAO concentration in serum and plasma using a high-throughput NMR clinical analyzer...
June 14, 2017: Clinical Biochemistry
https://www.readbyqxmd.com/read/28623662/advances-in-the-analysis-of-water-and-wastewater-samples-using-various-sensing-protocols-and-microfluidic-devices-based-on-pad-and-%C3%AE-tas-systems
#11
Krzysztof Piaskowski, Renata Świderska-Dąbrowska, Aleksandra Kaleniecka, Paweł K Zarzycki
The main goal of this review is to summarize practical approaches concerning the application of microfluidic systems for the analysis of various biomarkers and pollutants, as well as microbes, in water and wastewater matrixes. This problem involves multidisciplinary expertise combining research knowledge from various areas, including wet chemistry, biochemistry, physical chemistry, molecular biology, genetics, signal processing, microelectronics material science, and separation science. It has been documented that fairly primitive but fast and inexpensive screening methods involving paper-based analytical devices (PADs) and micro total analytical systems (μTAS) can be considered as serious alternatives to their more advanced counterparts such as GC, HPLC, and capillary electrophoresis coupled to various sophisticated detectors (e...
June 16, 2017: Journal of AOAC International
https://www.readbyqxmd.com/read/28623656/quantum-dots-as-components-of-electrochemical-sensing-platforms-for-the-detection-of-environmental-and-food-pollutants-a-review
#12
María Pedrero, Susana Campuzano, José M Pingarrón
The determination of organic and inorganic environmental and food pollutants is a key matter of concern in analytical chemistry due to their effects as a serious threat to human health. Focusing on this issue, several methodologies involving the use of nanostructured electrochemical platforms have been recently reported in the literature. Among these methods, those employing the use of quantum dots (QDs) stand out because of features such as signal amplification, good reproducibility and selectivity, and the possibility for multiplexed detection, and because they preserve the outstanding characteristics of electrochemical methodologies with respect to simplicity, ease-of-use, and cost-effective instrumentation...
June 16, 2017: Journal of AOAC International
https://www.readbyqxmd.com/read/28623653/miniaturized-temperature-controlled-planar-chromatography-micro-tlc-as-a-versatile-technique-for-fast-screening-of-micropollutants-and-biomarkers-derived-from-surface-water-ecosystems-and-during-technological-processes-of-wastewater-treatment
#13
Magdalena M Ślączka-Wilk, Elżbieta Włodarczyk, Aleksandra Kaleniecka, Paweł K Zarzycki
There is increasing interest in the development of simple analytical systems enabling the fast screening of target components in complex samples. A number of newly invented protocols are based on quasi separation techniques involving microfluidic paper-based analytical devices and/or micro total analysis systems. Under such conditions, the quantification of target components can be performed mainly due to selective detection. The main goal of this paper is to demonstrate that miniaturized planar chromatography has the capability to work as an efficient separation and quantification tool for the analysis of multiple targets within complex environmental samples isolated and concentrated using an optimized SPE method...
June 16, 2017: Journal of AOAC International
https://www.readbyqxmd.com/read/28623087/highly-multiplex-real-time-pcr-based-screening-for-blood-borne-pathogens-on-an-openarray-platform
#14
Elena Grigorenko, Carolyn Fisher, Sunali Patel, Valerie Winkelman, Phillip Williamson, Caren Chancey, Germán Añez, Maria Rios, Victoria Majam, Sanjai Kumar, Robert Duncan
Molecular diagnostics are increasingly used in the blood bank industry. A device that can combine simultaneous detection of multiple targets with the flexibility of inclusion of emerging pathogens is desirable for testing blood products. A highly multiplexed blood-borne pathogen panel (BBPP) using dual-label probe chemistry (TaqMan assays) was developed for simultaneous detection and discrimination of 17 viral pathogens in human plasma samples and 13 bacterial and protozoan pathogens in human blood samples on the OpenArray platform...
June 12, 2017: Journal of Molecular Diagnostics: JMD
https://www.readbyqxmd.com/read/28622801/rapid-determination-of-nitrate-in-vegetables-by-gas-chromatography-mass-spectrometry
#15
Beatrice Campanella, Massimo Onor, Enea Pagliano
In this study we present a novel isotope dilution gas chromatography method for the determination of nitrate in vegetables. The analyte was extracted in water at 70(∘)C and mixed with (15)N isotopically enriched nitrate internal standard. The sample was centrifuged and the supernatant reacted with sulfamic acid for removal of nitrite, and with triethyloxonium tetrafluoroborate for converting nitrate into volatile EtONO2. This simple aqueous chemistry allowed for separation of analyte from sample matrix in the form of a gaseous derivative which could be sampled in the headspace before GC-MS analysis...
August 8, 2017: Analytica Chimica Acta
https://www.readbyqxmd.com/read/28619938/kilogram-scale-prexasertib-monolactate-monohydrate-synthesis-under-continuous-flow-cgmp-conditions
#16
Kevin P Cole, Jennifer McClary Groh, Martin D Johnson, Christopher L Burcham, Bradley M Campbell, William D Diseroad, Michael R Heller, John R Howell, Neil J Kallman, Thomas M Koenig, Scott A May, Richard D Miller, David Mitchell, David P Myers, Steven S Myers, Joseph L Phillips, Christopher S Polster, Timothy D White, Jim Cashman, Declan Hurley, Robert Moylan, Paul Sheehan, Richard D Spencer, Kenneth Desmond, Paul Desmond, Olivia Gowran
Advances in drug potency and tailored therapeutics are promoting pharmaceutical manufacturing to transition from a traditional batch paradigm to more flexible continuous processing. Here we report the development of a multistep continuous-flow CGMP (current good manufacturing practices) process that produced 24 kilograms of prexasertib monolactate monohydrate suitable for use in human clinical trials. Eight continuous unit operations were conducted to produce the target at roughly 3 kilograms per day using small continuous reactors, extractors, evaporators, crystallizers, and filters in laboratory fume hoods...
June 16, 2017: Science
https://www.readbyqxmd.com/read/28616959/smelling-seeing-tasting-old-senses-for-new-sensing
#17
Luca Guerrini, Eduardo Garcia-Rico, Nicolas Pazos-Perez, Ramon A Alvarez-Puebla
The senses are the physiological mechanisms of perception that enable an organism to interact with the surrounding media. For centuries, humans have utilized these senses in science; vision and olfaction have been used the most extensively in laboratories followed by gustation and somatosensation, whereas audition has only rarely been employed. Most of these applications of senses were developed spontaneously based on the natural behavior of the chemistry of the reactants producing changes in scent, taste, or color...
June 27, 2017: ACS Nano
https://www.readbyqxmd.com/read/28615228/stronger-together-aggregated-z-values-of-traditional-quality-control-measurements-and-patient-medians-improve-detection-of-biases
#18
Andreas Bietenbeck, Markus A Thaler, Peter B Luppa, Frank Klawonn
BACKGROUND: In clinical chemistry, quality control (QC) often relies on measurements of control samples, and limitations, such as a lack of commutability, compromise the ability of such measurements to detect out-of-control situations. Medians of patient results have also been used for QC purposes, but it may be difficult to distinguish changes observed in the patient population from analytical errors. This study aims to combine traditional control measurements and patient medians for facilitating detection of biases...
June 14, 2017: Clinical Chemistry
https://www.readbyqxmd.com/read/28610424/single-molecule-chemistry-with-surface-and-tip-enhanced-raman-spectroscopy
#19
Alyssa B Zrimsek, Naihao Chiang, Michael Mattei, Stephanie Zaleski, Michael O McAnally, Craig T Chapman, Anne-Isabelle Henry, George C Schatz, Richard P Van Duyne
Single-molecule (SM) surface-enhanced Raman spectroscopy (SERS) and tip-enhanced Raman spectroscopy (TERS) have emerged as analytical techniques for characterizing molecular systems in nanoscale environments. SERS and TERS use plasmonically enhanced Raman scattering to characterize the chemical information on single molecules. Additionally, TERS can image single molecules with subnanometer spatial resolution. In this review, we cover the development and history of SERS and TERS, including the concept of SERS hot spots and the plasmonic nanostructures necessary for SM detection, the past and current methodologies for verifying SMSERS, and investigations into understanding the signal heterogeneities observed with SMSERS...
June 14, 2017: Chemical Reviews
https://www.readbyqxmd.com/read/28604846/identification-of-active-components-in-yixinshu-capsule-with-protective-effects-against-myocardial-dysfunction-on-human-induced-pluripotent-stem-cell-derived-cardiomyocytes-by-an-integrative-approach
#20
Minyu Zhang, Hongwei Wu, Feifei Guo, Yangyang Yu, Junying Wei, Ya Geng, Shifeng Wang, Shiyou Li, Hongjun Yang
Traditional Chinese medicine (TCM) preparations have significant effects on some refractory diseases; however, these compositions are complex and their mechanisms are unknown. Identification of the active components in these preparations is essential. The mortality rate for heart failure (HF) has been increasing in recent years, and myocardial dysfunction (MD) has been proved to be the pathological basis of HF. Yixinshu Capsule (YXSC) is a multi-component oral drug with therapeutic effects on HF. However, the key active components are still unclear...
June 12, 2017: Molecular BioSystems
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