Critical reviews in analytical chemistry最新文献

Boswellia resin is an exudate from the cut bark of Boswellia trees. The main constituents of pharmacological interest are boswellic acids (pentacyclic triterpenoids), namely α-boswellic acid, β-boswellic acid, 3-O-acetyl-α-boswellic acid, 3-O-acetyl-β-boswellic acid, 11-keto-β-boswellic acid, and 3-O-acetyl-11-keto-β-boswellic acid. Nowadays, dietary supplements with Boswellia serrata extract are used in the treatment of inflammatory joint diseases. Additionally, the constituents of Boswellia resin have shown potential for the treatment of other chronic inflammatory diseases and various types of cancer. Separation methods including ultra/high-performance liquid chromatography, gas chromatography, thin layer chromatography, supercritical fluid chromatography, and capillary electrochromatography coupled with UV or MS detection have been used for the determination of boswellic acids in various matrices (mostly plant material and biological samples). This review aims to provide a comprehensive summary of these separation methods, offering a critical discussion of their strengths and limitations in the analysis of boswellic acids. The knowledge of various separation methods plays a pivotal role in the quality control of herbal dietary supplements and the monitoring of the metabolism and pharmacokinetics of their constituents. The approaches based on metabolomics and network pharmacology represent new ways of fingerprinting secondary metabolites in Boswellia resin increasing the comprehensiveness of the output of these methods resulting in safer dietary supplements.

Catecholamines (CAs), which include adrenaline, noradrenaline, and dopamine, are neurotransmitters and hormones that critically regulate the cardiovascular system, metabolism, and stress response in the human body. The abnormal levels of these molecules can lead to the development of various diseases, including pheochromocytoma and paragangliomas, Alzheimer's disease, and Takotsubo cardiomyopathy. Due to their low cost, high sensitivity, flexible detection strategies, ease of integration, and miniaturization, electrochemical techniques have been extensively employed in the detection of CAs, surpassing traditional analytical methods. Electrochemical detection of CAs in real samples is challenging due to the tendency of poisoning electrode. Chemically modified electrodes have been widely used to solve the problems of poor sensitivity and selectivity faced by bare electrodes. There are a few articles that provide an overview of electrochemical detection and efficient enrichment of CAs, but there is a dearth of updates on the role of CAs in the pathogenesis of diseases. Additionally, there is still a lack of systematic synthesis with a focus on modified electrodes for electrochemical detection. Thus, this review provides a summary of the recent clinical pathogenesis of CAs and the modified electrodes for electrochemical detection of CAs published between 2017 and 2022. Moreover, challenges and future perspectives are also highlighted. This work is expected to provide useful guidance to researchers entering this interdisciplinary field, promoting further development of CAs pathogenesis, and developing more novel chemically modified electrodes for the detection of CAs.

The number of pollutants and chemicals with the potential to reach the environment is still largely unknown, which poses great challenges for researchers in various fields of science, environmental scientists, and analytical chemists. Chromatographic techniques, both gas chromatography (GC) and liquid chromatography (LC) coupled with different types of detection, are now invaluable tools for the identification of a wide range of chemical compounds and contaminants in water. This review is devoted to chromatographic techniques GC-MS, GC-Orbitrap-MS, GC-MS/MS, GC-HRMS, GC × GC-TOFMS, GC-ECD, LC-MS/MS, HPLC-UV, HPLC-PDA, UPLC-QTOFMS, used to determinate emerging organic contaminants in aquatic media, mainly in urban water, published in the scientific literature over the past several years. The article also focuses on sample preparation methods used in the analysis of aqueous samples. Most research focuses on minimizing the number of sample preparation steps, reducing the amount of solvents used, the speed of analysis, and the ability to apply it to a wide range of analytes in a sample. This is extremely important in the application of sensitive and selective methods to monitor the status of urban water quality and assess its impact on human health.

Frustrated Lewis pairs (FLPs) have been widely investigated as promising catalysts due to their metal-free feature and ability to activate small molecules. Over the last few years, the structure, dynamics and interactions between the Lewis centers and their effects on the reactivity with different substrates have been studied. Nuclear magnetic resonance (NMR) is a powerful tool in studying the reaction intermediates, kinetics and mechanism of frustrated Lewis pairs (FLPs). Various NMR experiments have been applied to precisely determine the association or cooperativity of FLPs and one or two-dimensional spectra were obtained. Herein, insights coming from NMR spectroscopy for FLPs are presented, the structure and reactivity of FLPs in solution are described, and their effects on the kinetics and mechanism of different substrates are also illustrated in this review.

The suitability and applications of Total reflection X-ray Fluorescence (TXRF) for characterization of nuclear materials are numerous. TXRF has been successfully applied for trace, minor and major determinations of constituents in nuclear materials such as fuel, clad, control rod, coolant, etc. The two major advantages of TXRF i.e. requirement of very small sample for analysis and non-requirement of matrix matched standards, make this technique further more attractive and suitable for nuclear industry. The applications of TXRF for trace analysis in nuclear materials such as fuel, clad, coolant and control rods are described in detail along with its applications for determination of major and speciation studies in TXRF mode.

Vitamin D deficiency is thought to be associated with a wide range of diseases, including diabetes, cancer, depression, neurodegenerative diseases, and cardiovascular and cerebrovascular diseases. This vitamin D deficiency is a global epidemic affecting both developing and developed countries and therefore qualitative and quantitative analysis of vitamin D in a clinical context is essential. Mass spectrometry has played an increasingly important role in the clinical analysis of vitamin D because of its accuracy, sensitivity, specificity, and the ability to detect multiple substances at the same time. Despite their many advantages, mass spectrometry-based methods are not without analytical challenges. Front-end and back-end challenges such as protein precipitation, analyte extraction, derivatization, mass spectrometer functionality, must be carefully considered to provide accurate and robust analysis of vitamin D through a well-designed approach with continuous control by internal and external quality control. Therefore, the aim of this review is to provide a comprehensive overview of the development of mass spectrometry methods for vitamin D accurate analysis, including emphasis on status markers, deleterious effects of biological matrices, derivatization reactions, effects of ionization sources, contribution of epimers, standardization of assays between laboratories.

Limiting and preventing oral diseases remains a major challenge to the health of populations around the world, so finding ways to detect early-stage diseases (e.g., caries, periodontal disease, and oral cancer) and aiding in their prevention has always been an important clinical treatment concept. The development and application of electrochemical detection technology can provide important support for the early detection and non-invasive diagnosis of oral diseases and make up for the shortcomings of traditional diagnostic methods, which are highly sensitive, non-invasive, cost-effective, and less labor-intensive. It detects specific disease markers in body fluids through electrochemical reactions, discovers early warning signals of diseases, and realizes rapid and reliable diagnosis. This paper comprehensively summarizes the development and application of electrochemical biosensors in the detection and diagnosis of common oral diseases in terms of application platforms, sensing types, and disease detection, and discusses the challenges faced by electrochemical biosensors in the detection of oral diseases as well as the great prospects for future applications, in the hope of providing important insights for the future development of electrochemical biosensors for the early detection of oral diseases.

The inherent complexity of biological matrices and presence of several interfering substances in biological samples make them unsuitable for direct analysis. An effective sample preparation technique assists in analyte enrichment, improving selectivity and sensitivity of bioanalytical method. Because of several key benefits of employing 3D printed sorbent in sample extraction, it has recently gained popularity across a variety of industries. Applications for 3D printing in the field of bioanalytical research have grown recently, particularly in the areas of miniaturization, (bio)sensing, sample preparation, and separation sciences. Due to the high expense of the solid phase microextraction cartridge, researcher approaches in-lab production of sorbent material for the extraction of analyte from biological samples. Owing to its distinct advantages such as low costs, automation capabilities, capacity to produce products in a variety of shapes, and reduction of tedious steps of sample preparation, 3D printed sorbents are gaining increased attention in the field of bioanalysis. It is also reported to offer high selectivity and assist in achieving a much lower limit of detection. In this review, we have discussed current advancements in different types of 3D printed sorbents, production methods, and their applications in the field of bioanalytical sample preparation.

Withanolides are the class of steroidal molecules getting greater emphasis in recent years. Quality control throughout the manufacturing and storage period is often one of the key problems that have restricted their broad use in India's indigenous and Ayurvedic medical systems for thousands of years. Because of their diverse clinical potential, withanolides have received a great deal of scientific attention. Analytical techniques are being devised for the automated isolation, identification, and estimation of every single protein within the cell as well as in herbal extracts of withanolides, due to which now researchers are interested in determining the effects of metabolism as well as various stimuli on protein expression, which made the study easier. This study discusses the potential use of hyphenated analytical methods that are reliable in understanding the molecular signaling features, proteome evaluation and characterization of withanolides, in addition to examining existing methodological limitations. The choice of analytical techniques for the withanolides analysis, however, relies on the nature of the sample matrix, the aim of the analysis, and the sensitivity of the technique.

Quality consistency evaluation of traditional Chinese medicines (TCMs) is a crucial factor that determines the safe and effective application in clinical settings. However, TCMs exhibit diverse, heterogeneous, complex, and flexible chemical compositions, as well as variability in preparation processes. These characteristics pose greater challenges in researching the consistency of TCMs compared to chemically synthesized and biological drugs. Therefore, it is paramount to develop effective strategies for evaluating the quality consistency of TCMs. From the starting point of quality properties, this review explores the strategy used to evaluate quality consistency in terms of chemistry-based strategy (chemical consistency) and the biology-based strategy (bioequivalence). Among them, the chemistry-based strategy is the mainstream, and biology-based strategy complements the chemistry-based strategy each other. Furthermore, the emerging chemistry-biology strategies (overall evaluation) is discussed, including individually combining strategy and integration strategy. Finally, this review provides insights into the challenges and future perspectives in this field. By highlighting current status and trends in TCMs quality consistency, this review aims to contribute to establishment of generally applicable chemistry-biology integrated evaluation strategy for TCMs. This will facilitate the advancement toward a higher stage of overall quality evaluation.