Critical reviews in analytical chemistry最新文献

The catecholamine neurotransmitter dopamine is critical in regulating various physiological functions associated with the human central nervous system. Abnormal levels of dopamine in the body can lead to various medical and behavioral conditions. Electrochemical sensors are excellent tools for quantifying dopamine levels in the body due to their sensitivity, lower detection limits, easy operating procedures, and low cost. Chemically modified electrodes are widely used for dopamine detection. Among them, the usefulness of transition metal complexes as electrode modifiers is apparent from their unique structural and electronic features, which resemble active sites of many enzymes. Over the last decade, efforts have been made to develop electrodes immobilizing transition metal complexes for biomolecule sensing. The metal ion and the chosen ligand fundamentally influence the applicability of the sensor. This review provides an overview of the metal complex immobilization strategies as well as various sensors developed for detecting dopamine using transition metal complexes.

Non-fouling refers to the prevention of undesirable biological or chemical reactions on sensing surfaces, which enhances the performance of sensing systems. Biofouling poses a significant challenge in achieving specific interactions in biosensors, particularly in the context of serological biomarker analysis. When analyzing clinical samples, implementing anti-biofouling measures is crucial. However, the criteria for selecting appropriate anti-biofouling options remain inadequately defined. To overcome these issues, the significance of blocking agents on bioreceptor-modified surfaces to enhance specificity is emphasized. Besides, titanium dioxide (TiO₂) nanomaterial-hybrid biosensors have been desired for analyzing human serological biomarkers, as TiO₂ enhances the non-fouling nature of sensing surfaces. TiO₂ is a semiconductor material used in biosensing applications due to its high surface area, excellent chemical stability, and biocompatibility. To utilize TiO₂ in a non-fouling environment, surface modifications have been implemented to reduce the undesirable adhesion of biological molecules. Biosensors based on TiO₂ nanomaterials have exhibited remarkable sensitivity and specificity, along with rapid detection capabilities. These TiO₂ biosensors can analyze human serum in as little as 2 s, achieving average sample concentrations in the nanomolar range and a correlation coefficient of 0.99. This overview provides an update on TiO₂ electrical biosensors for detecting serological markers and demonstrating excellent performance in clinical diagnosis. Besides, discusses unresolved issues, including the limitations of electrical biosensors in real-time point-of-care applications and the importance of Internet of Things.

The extraction method is important in analytical processes. Therefore, various extraction methods, including traditional methods and modern techniques such as microextraction methods, have been developed. Microextraction methods have been developed as an effective, green, low-cost alternative to overcome the limitations of traditional methods. Stir bar sorptive extraction (SBSE) is an extraction technique for the enrichment of volatile and semi-volatile organic materials from aqueous and gaseous matrices. Given the need for sample pretreatment techniques that are sensitive, green, and reproducible, SBSE is proposed as a suitable and effective method. In this method, a magnetic stir bar coated with a layer of polydimethylsiloxane (PDMS) or other sorbents is inserted into the solution containing the sample. During stirring, the target compounds are distributed between the liquid phase and the sorbent. This method is simple and solvent-free and can be used to extract very small amounts of analytes from various matrices. One of the important points in the SBSE is its combination with mass spectrometry (MS). SBSE-MS is a powerful technique for analyzing a wide range of target analytes, which provides significant advantages such as high reproducibility, high sensitivity and suitable enrichment, environmental compatibility and usability in analytical devices such as liquid chromatography (LC) and gas chromatography (GC). The present review aims to discuss the principle of SBSE and the developments which have occurred in coatings and practical implementations in recent years. This review introduced all the presented which can be used to improve the applicability of different coatings for the extraction of analytes.

"Tusi," commonly known by various names such as "pink cocaine," "cocaina rosada," "Tucibi," "pink powder," "Eros," and "Venus," is a psychoactive mixture of substances that first appeared in Colombia around 2010. Since its emergence, its use has expanded across Latin America, the United States, Australia, parts of Southeast Asia and Europe, with notable prevalence in Spain. The composition of "Tusi" is highly variable and often unpredictable, leaving users unaware of its exact chemical constitutes and the associated pharmacological and physiological risks. Frequently mischaracterized as a solely product of the 2 C class of phenethylamines, it is typically a mixture of ketamine, 3,4-methylenedioxymethamphetamine (MDMA), amphetamine (AMP), methamphetamine (MAMP), and occasionally cocaine, opioids, or other new psychoactive substances (NPS). Notably, in Australia, 133 kg of "pink cocaine" were seized in 2024, with ketamine and MDMA purities ranging from 6.8% to 51.3% and 15.8% to 33.2%, respectively. Additionally, in the US, the Drug Enforcement Administration (DEA) has seized 960 samples of "Tusi" since 2020. Of these, only four were confirmed to contain 2,5-dimethoxy-4-bromophenethylamine (2 C-B), which is the most anticipated compound from the 2 C family. Given its widespread global availability and the scarcity of scientific literature on this mixture, this critical review aims to present a detailed profile of "Tusi". It examines its composition, its associated health risks, and the current methodologies employed for its detection. Additionally, it addresses the challenges related to its analysis and proposes alternative societal monitoring strategies, such as the application of drug-use biomarkers in wastewater streams.

Contaminant residues in food and drinking water pose a significant threat to human health. Therefore, high-performance, on-site analytical methods are essential for effectively monitoring and controlling this risk. In recent years, photothermal lateral flow immunoassay (LFIA) has garnered considerable attention as a point-of-care testing (POCT) method due to its rapid responsiveness, cost-effective portable instrumentation, and operational simplicity. In this context, considerable efforts have been dedicated to advancing photothermal LFIAs for food safety and control. This review aims to summarize the principles and assay formats of LFIAs, along with the sensing mechanisms underlying photothermal LFIAs. Furthermore, it provides an overview of recent developments in the functional modification of photothermal materials within LFIA systems for detecting harmful substances in food, including pathogenic bacteria, mycotoxins, hazardous organic pollutants, veterinary drug residues, and other organic contaminants. Additionally, the future directions and recent challenges hindering the practical application of photothermal LFIAs are briefly summarized.

Neurodegenerative disorders (NDD) i.e., dementia of the Alzheimer's type, Parkinson's disease, Huntington's disease, and amyotrophic lateral sclerosis are a rising worldwide epidemic driven by aging populations and characterized by progressive neuronal impairment. In the face of symptomatic therapies, disease-modifying treatments are beyond reach, for many years, at least, owing to the multifactorial origin, including protein aggregation, oxidative stress, neuroinflammation, and neurotransmitter dysregulation. Here, we point out thiophene, a five-membered heterocyclic sulfur-containing scaffold, as an underinvestigated but highly versatile pharmacophore with great potential in therapeutics of NDD. Here, we provide a systematic review of thiophene derivatives identified between 2006 and 2024, highlighting that these compounds are capable of modulating the aggregation of amyloid-β, inhibiting acetylcholinesterase, alleviating oxidative stress, inhibiting the toxicity of α-synuclein, and restoring neurotransmitter homeostasis. Specific emphasis is placed on their structural malleability, blood-brain barrier penetrability, and multi-targeting, which collectively present advantages over traditional heterocyclic templates. Progress in the areas of structure-activity relationship (SAR)-motivated design, synthetic methods, molecular docking, and preclinical assessment is reviewed, leading to the establishment of lead thiophene scaffolds with micro or nanomolar-range activity. This review also provides future directions, such as the requirement of pharmacokinetic improvement, target verification, and translational research to bridge preclinical discoveries with clinical utility. This article collectively places thiophene derivatives as an innovative chemical platform for the design of next-generation drugs for neurodegenerative diseases.

Surfactant is usually considered the key component to form microemulsion. surfactant-based microemulsion (SBME) can also be called traditional microemulsion. It has a wide range of applications. It has the advantages of high treatment efficiency and low energy consumption in oily sludge treatment. However, the latest research found that even without traditional surfactants, microemulsions can be synthesized through a three-phase system consisting of two immiscible liquids and one "amphiphilic solvent." This new type of microemulsions is named "surfactant free microemulsion" (SFME). The so-called parental solvents refer to those solvents that can be completely or partially mixed with two immiscible solutions. SFME is similar to the traditional SBME in structure and properties, but SFME makes up for the shortcomings of the traditional microemulsions in many aspects. The application of advanced SFME is still in the exploratory stage, and in the future SFME may replace SBME in various treatment technologies similar to oily sludge treatment. This article reviews the latest research progress in the field of SFME, covering its phase behavior, structural characteristics, property analysis, oilfield applications, and potential application areas. In addition, the microemulsions' system does not have to use water as the polar solution. At present, many articles have developed anhydrous surfactant-free microemulsions.

The miniaturization of separation platforms marks a transformative shift in analytical science, merging microfabrication, automation, and intelligent data integration to meet rising demands for portability, sustainability, and precision. This review critically synthesizes recent technological advances reshaping the field-from microinjection and preconcentration modules to compact, high-sensitivity detection systems including ultraviolet-visible (UV/Vis), fluorescence (FL), electrochemical detection (ECD), and mass spectrometry (MS). The integration of microcontrollers, AI-enhanced calibration routines, and IoT-enabled feedback loops has led to the rise of self-regulating analytical devices capable of real-time decision-making and autonomous operation. Additive manufacturing further accelerates innovation by enabling rapid prototyping and customization through three-dimensional (3D) printing of entire Laboratory-on-Chip (LOC) systems, detectors, and embedded electrodes. Despite these advances, several critical challenges remain. Issues in flow stability, sample compatibility, standardization, and long-term reliability continue to hinder widespread deployment in real-world environments. This review highlights both technical breakthroughs and unresolved limitations across pharmaceutical, environmental, clinical, forensic, and food safety domains. Special emphasis is placed on the convergence of hardware miniaturization with smart software architectures to create adaptive, scalable platforms. Looking ahead, future systems must prioritize interoperability, energy efficiency, and AI-guided control to realize the full potential of decentralized analytical diagnostics. Ultimately, the next generation of separation science will be shaped not only by miniaturization-but also by intelligent design, sustainable engineering, and integrative system thinking.

An innovative treatment for schizophrenia has been approved by the U.S. Food and Drug Administration, which combines the muscarinic antagonist trospium chloride with the muscarinic agonist xanomeline. It is a new therapeutic option that attacks the fundamental neurobiology of schizophrenia in a fresh way. A negligible portion of people worldwide suffer from schizophrenia, a persistent and crippling mental illness. The disorder has a major influence on everyday functioning and quality of life. Antipsychotic drugs have significant adverse effects, although they are often beneficial. Furthermore, they frequently have minimal effects on the negative and cognitive symptoms of schizophrenia. In the absence of the typical adverse effects of dopamine-targeting antipsychotics, combination therapy with xanomeline and trospium chloride has shown notable effectiveness in lowering both positive and negative symptoms of schizophrenia. A careful review of the literature revealed that no analytical method for estimation has been developed for this combination of medications. The current article examines the analytical techniques that are available for each drug separately, which may help researchers create an analytical technique that takes into account the importance of each drug in combination.

It is imperative to evaluate the environmentally conscious sample preparation techniques, as they involve the use of a variety of solvents, such as organic compounds, substances, sorbents, pH modifications, and energy inputs. Pressurized fluid extraction, liquid-liquid microextraction, accelerated solvent extraction, microwave-assisted extraction, and dispersive solid-phase extraction are among the numerous extraction methods that are employed to extract sulfonamide due to its sensitivity, efficacy, speed, versatility, and economic appeal. The greenness and sustainability of 20 methods for detecting sulfonamide in environmental, biological, and dietary samples are compared in this article using an Analytical GREEnness prep (AGREE prep), Sample Preparation Metric of Sustainability (SPMS), Blue Applicability Grade Index (BAGI), and Click Analytical Chemistry (CAC) metrics. This assessment provides substantial new information regarding the environmental consequences and sustainability of sulfonamide analysis in the preparation of samples for solid phase extraction (SPE) using HPLC and HPLC-MS/MS methods. Among these, HPLC method developed by Luo et al. & Ma et al. and LC-MS/MS method proposed by García-Galán et al. & Jian et al. reconcile analytical effectiveness with environmental sustainability since they consume less energy, are reusable, encompass fewer processes, and have minimal waste management. These features have been attributed to low energy use, excessive sample production, less waste, and environmentally suitable solvents.