Critical reviews in analytical chemistry最新文献

This review discusses various sample pretreatment methods for the analytical assessment of endocannabinoids in biological fluids and tissues. Techniques like liquid-liquid extraction, protein precipitation, SALLE, SPME, and micro-solid phase extraction (µ-SPE) are investigated. The findings show that SALLE and SPME provide phase separation as a fast and environmentally friendly method and allow high sensitivity in the analyses. The analysis of endocannabinoids, particularly, 2-AG, is challenging due to its tendency to isomerize into 1-AG and its lack of stability. These challenges are highlighted, emphasizing the need for optimized analytical methods to ensure accurate and reliable results. In conclusion, this study demonstrates the applicability of effective extraction techniques as an alternative to traditional methods to obtain reliable results in endocannabinoid analyses and provides a new perspective to the literature.

Hydrogen peroxide (H₂O₂) is suspected to promote cancer. Higher concentrations of H₂O₂ have always harmed mammalian cells, other living things, as well as the environment. As well, elevated concentrations of H₂O₂ might cause major health problems such as cancer, cardiovascular disease, asthma, Alzheimer's disease, etc. As all, bioanalysis, environmental protection, and food security are needed for the rapid and accurate sensing of H₂O₂. For the sensing of H₂O₂, nanoparticle construction of carbon-based sensors has been used. Zero-dimensional (0D) nanostructures or nanosized designs of carbon-based fluorescent probes such as graphene quantum dots (GQDs) and carbon quantum dots (CQDs/CDs) are gaining popularity in sensing. Therefore, this review focused on current developments in sensing systems made possible by innovative applications of GQDs with CQDs, with a focus on how these materials significantly enhance overall H₂O₂ detection. In brief, the review article focuses on the basic insights of H₂O₂ and carbon-based nanomaterials. After this, the use of GQDs and CQDs-based sensors for H₂O₂ detection is discussed in a brief period from 2015 to 2024. At last, the current challenges, future prospects, and concluding remarks have been added. As an outcome, GQDs and CQDs showed the potential for sensing H₂O₂ because of their distinctive electrical, fluorescent, photoluminescent, chemiluminescent, and electrochemiluminescent features. Carbon-based sensors for the recognition of H₂O₂ utilized a variety of methods, counting PET, IFF, static quenching, dynamic quenching, FRET, etc. As an outcome, it appears that carbon-based nanoscale sensors offered potential options for highly effective yet precise sensors for the detection of H₂O₂. In winding up, the GQDs and CQDs-based sensing nanosystems provide a new platform for the recognition of H₂O₂ that can open an innovative era for the diagnosis of health issues as well as monitor several environmental processes and issues at the point of care.

Paraquat (PQ) is a potent and widely utilized herbicide known for its effectiveness in controlling a broad spectrum of weeds. Its chemical properties make it an invaluable tool in agriculture, where it helps maintain crop yields and manage invasive plant species. However, despite its benefits in weed management, PQ poses significant risks due to its severe toxicity, which affects multiple organ systems in both humans and animals. The dual nature of PQ, as both a valuable agricultural chemical and a hazardous toxicant, necessitates a comprehensive understanding of its toxicological impacts and the development of effective detection and development strategies. This review aims to provide a comprehensive overview of PQ-induced toxicities, including neurotoxicity, lung toxicity, liver toxicity, kidney toxicity, and immunotoxicity. By synthesizing current knowledge on PQ health impacts, highlighting epidemiological trends, and exploring recent advancements in colorimetric and fluorimetric detection methods, this review seeks to contribute to the development of strategies for improving public health outcomes and enhancing our ability to manage the risks associated with PQ exposure. Addressing PQ toxicity through a multidisciplinary approach, incorporating toxicological, epidemiological, and technological perspectives, is essential for safeguarding health and promoting effective interventions.

Fluorescent sensors reflect information such as the concentration or content of the analysis by interacting with a specific recognition group to change the signal of the fluorophore. It has attracted much attention because of its advantages of high sensitivity, fast detection speed and low cost, and it has become an effective alternative to traditional detection methods. Graphitic phase carbon nitride nanosheets (g-CNNs) are a class of carbon-based fluorescent nanomaterials derived from bulk graphite phase carbon nitride (g-C₃N₄), which have attracted much attention from scholars because of their advantages of low cost, simple fabrication, high quantum yield, strong stability and nontoxicity. Functional modified g-CNNs can greatly improve the photocatalytic performance. At present, although there have been some researches on fluorescent sensors based on g-CNNs. Nevertheless, there are few reviews about the g-CNNs-based fluorescent sensors. Therefore, in addition to summarizing the sensing mechanism of fluorescent sensors (such as photoinduced electron transfer, fluorescence resonance energy transfer, and intramolecular charge transfer) and the advantages and disadvantages of common signal substances, this paper focused on the application progress of g-CNNs-based fluorescent sensors in the field of analysis and detection.

Though metal ions like copper, iron, zinc, etc. are essential, but their dyshomeostasis is associated with several disorders. Therefore, fast, sensitive, and cost-effective monitoring of these cations will have a significant impact. Many recently reported small organic molecules were able to detect a specific metal ion because of certain variations in the electron/charge transfer processes occurring in those molecules after binding with metal ions. In this context, Schiff base molecules were widely used as fluorescence turn-on/turn-off probes for the detection of metal ions like Al³⁺, Cu²⁺, Zn²⁺, Fe³⁺, Ag⁺, heavy metal ions, etc. In this article, we have reviewed the recent developments in fluorimetric chemosensing of metal ions by Schiff bases based on the photo-induced electron transfer (PET) process. A variety of examples have been discussed in which PET was used as a cation recognition mechanism. Particular focus is placed on the molecular probes used for sensing, including their design, selectivity, sensitivity, and in some cases their potential bioimaging applications.

The physiological and officinal functions of phytosterols are of great significance, and recent dietary guidelines have underscored the significance of incorporating them into a balanced diet. Furthermore, it exhibits inhibitory effects on tumor growth, stimulates cellular immunity, possesses anti-inflammatory, antioxidant, and antidiabetic properties. To gain a more comprehensive understanding of the role of phytosterols in public health, it is crucial to establish simple, rapid, eco-conscious, efficient, and highly sensitive techniques for their extraction and determination across various matrices. This review presents a thorough overview of various techniques used for extracting and analyzing phytosterols in diverse plant-derived foods, encompassing a range of advanced technologies like solid-phase extraction, microextraction, supercritical fluid extraction, QuEChERS, alongside traditional approaches. The detection techniques include liquid chromatography-based methods, gas chromatography-based methods, supercritical fluid chromatography, and other methodologies. Additionally, we conduct a thorough examination and comparison of various techniques while proposing future prospects.

Quantitative analysis of peptides in biological fluids offers a high diagnostic and prognostic tool to reflect the pathophysiological condition of the patient. Recently, methods based on liquid chromatography coupled with mass spectrometry (LC-MS) for the quantitative determination of intact peptides have been replacing traditionally used ligand-binding assays, which suffer from cross-reactivity issues. The use of "top-down" analysis of peptides is rapidly increasing since it does not undergo incomplete or non-reproducible digestion like "bottom-up" approaches. However, the low abundance of peptides and their peculiar characteristics, as well as the complexity of biological fluids, make their quantification challenging. Herein, the analytical pitfalls that may be encountered during the development of an LC-MS method for the analysis of intact peptides in biological fluids are discussed. Challenges in the pre-analytical phase, stability after sampling and sample processing, significantly impact the accuracy of peptide quantification. Emerging techniques, such as microextractions, are becoming crucial for improved sample cleanup and enrichment of target analytes. A comparison between the roles of high-resolution and low-resolution mass spectrometry in the quantification of intact peptides, as well as the introduction of supercharging reagents to enhance ionization, will be discussed.

The compositions of natural products are diverse and complex, which makes accurate analysis a challenging task. Surface-enhanced Raman spectroscopy (SERS) provides a means for the analysis of natural products. This review thoroughly examines the applications of SERS in the field of natural products, ranging from component identification and quality control to the clarification of mechanisms of action. It emphasizes SERS' capability to identify active ingredients in complex mixtures and monitor production for quality assurance. SERS can also elucidate the mechanisms of action. Nevertheless, challenges such as substrate standardization and the complexity of data processing exist. Future development will focus on innovative design, automation, and integration. Through continuous innovation and interdisciplinary collaboration, SERS is expected to play a crucial role in natural product research and development, further promoting the growth of the natural product industry. This review aims to provide a comprehensive perspective and support for natural product quality control and new drug development.

An overview of the latest advances in the design of electrochemical sensor architectures dedicated to the determination of drugs from the statin class is presented in this review. Statins are drugs widely consumed for cholesterol control, and their determination in different matrices through the application of electroanalysis is growing considering advantages such as operational simplicity, lower cost and ease of sample preparation. Within the context of statins, electrochemical sensor architectures can be subdivided into conventional/classical electrodes such as glassy carbon electrodes, carbon paste electrodes, pencil graphite electrodes, boron-doped diamond electrodes and metallic electrodes, and more modern electrode systems, including the screen-printed electrodes and 3D-printed electrodes. Thus, different aspects related to the preparation of these electrochemical sensors and analytical performance are presented, also reflecting advances in terms of designs of new architectures and possible improvements not previously reviewed. Analyzed samples, advantages and disadvantages of different implemented sensor's modification strategies and perspectives for the electroanalysis of statins are also included throughout the work.

Aroma is one of the important indexes to evaluate food quality. The formation of food aroma is based on the interaction of complex substances. The accurate quantification of aroma substances in food has significance in the analysis of aroma substances in food. In this review, the basic principle and significance of stable isotope dilution analysis is introduced, general steps for flavor analysis and its historical progress in food flavor analysis is discussed. Additionally, the application progress of stable isotope dilution analysis in food flavor analysis from 2019 to 2023 has been described in detail, which is also categorized by food. Finally, the accuracy and superiority of stable isotope dilution analysis as an accurate quantitative analysis method were discussed.