Trends in Environmental Analytical Chemistry最新文献

Advances in nanofabrication, instrumentation, miniaturization, and particularly the increased interdisciplinary dialogue between spectroscopists and their subscribers (biologists, environmentalists, and clinicians) have accelerated the application of surface-enhanced infrared absorption spectroscopy (SEIRAS) to biochemical analysis. This review outlines the basic principles of SEIRAS and its application to biochemical analysis in recent years. The review also comprehensively describes how SEIRAS can identify and quantify the biochemical activities of small molecules, biomacromolecules, and microorganisms, and summarizes the application trends of SEIRAS-based analytics and the value of SEIRAS information in modern biochemical applications and processes. Finally, it discusses the current challenges in SEIRAS-based biochemical analysis and proposes perspectives for further research in this field. Ultimately, the review aims to bridge the knowledge gap and promote further progress in SEIRAS-based biochemical analysis.

This review article focuses on various fabrication strategies that utilize amino acids (AAs) in the creation of electrochemical sensors designed for the detection of heavy metals (HMs). AAs possess unique characteristics that make them valuable materials for sensing heavy metal ions (HMIs). The article delves into how AAs are incorporated into sensor designs and their interactions with HMIs. It places particular emphasis on a range of electrode modification methods, including drop casting, self-assembled monolayers (SAMs), electropolymerization, and molecularly imprinted polymers (MIPs). The article provides a comprehensive discussion of the preparation procedures, mechanisms, as well as the advantages and disadvantages associated with each approach. Furthermore, it explores the emerging insights into combining AAs with both organic and inorganic materials, highlighting their synergistic effects in sensing applications. Throughout the review, the challenges and opportunities in the development of electrochemical sensors are spotlighted, with the ultimate goal of advancing next-generation sensors that can make a meaningful impact on modern society.

Per/polyfluoroalkyl substances (PFASs) are a class of ubiquitous environmental contaminants associated with several adverse health effects in humans and animals. Liquid chromatography with tandem mass spectrometry (LC-MS/MS) has traditionally been used to provide targeted quantitation of PFASs in biological samples. The analyte lists covered by targeted LC-MS/MS methods have grown rapidly as more PFASs have been discovered, though not all organofluorine is amenable to this technique. Integrative techniques measuring total organofluorine (TOF) coupled with LC-MS/MS analysis demonstrate that a significant fraction of TOF in biological samples is not captured by LC-MS/MS. This missing organofluorine may be contributed by PFASs that are not amenable to typical PFAS analytical conditions. Here, we review recent progress in quantifying total PFAS burden and identifying the compounds that comprise the unidentified organofluorine fraction (UOF), with a focus on human biological samples. While LC coupled to high-resolution mass spectrometry (LC-HRMS) has identified several novel PFASs in biological samples, these efforts do not appear to fully explain UOF content. Closing the UOF gap will necessitate the development of additional analytical approaches to broaden the chemical space captured by PFAS analysis. We highlight the use of additional chromatographic methods, advanced separation approaches such as ion mobility spectrometry (IMS), and continued improvement of HRMS semi-quantitation methods as promising paths forward to close the UOF gap.

Catechol (CC), an important phenolic compound, poses a significant threat to human health due to its toxicity and is widely available in natural water resources. In addition, CC is the most researched compound found in plenty of plant-based foods and beverages, including fruits, vegetables, grains, beans, and beer, tea, coffee, and wine. Therefore, developing effective, reliable, and robust methods for CC detection is critical. Among the sensor technologies; Electrochemical sensors are of great interest due to their simple equipment requirement, low cost, fast reaction possibilities, and fast response times. However, to produce more reliable and repeatable signals with high selectivity and sensitivity, it is crucial to modify the electrode surfaces, which are an indispensable element of electrochemical sensors. Recently, the use of various materials as electrode modification agents due to their superior chemical, physical and biological properties has significantly impacted electrochemical sensor and biosensor applications. In this review, the latest developments in the production of carbon material, conductive polymer, metal, and nanoparticle-based electrochemical sensors, and biosensors prepared by green synthesis techniques for CC detection within the scope of environmental monitoring applications are presented for the first time. It is important to synthesize materials with superior properties and critical significance in environmentally friendly applications by green principles. Within the scope of this study, environmental monitoring, the importance of CC detection, green synthesis methods, and barriers and solutions for CC sensing were examined, respectively. In addition to this, the role of the materials prepared by the green synthesis technique in the electrochemical detection of CC and the modification strategies are discussed in depth. Finally, opportunities and suggestions for advancing the field of next-generation sensor applications for CC detection are discussed.

Magnetic covalent organic frameworks (MCOFs) are a new class of emerging material as a super-effective magnetic adsorbent in analytical chemistry, particularly for environmental analysis, due to their outstanding features such as special morphology, cost-effective synthesis, chemical and thermal stability, a large specific surface area, high adsorption capacity, strong π-π interactions with analytes, uniform pore size, high reusability, and facile magnetic recovery. Based on the current research, after describing the diverse synthesis methods of MCOFs with various geometries that give them their unique physicochemical properties, this review emphasizes the great potential applications of MCOFs as an adsorbent in the magnetic solid phase extraction method in environmental analysis for pesticide residues, polycyclic aromatic hydrocarbons, drugs, endocrine-disrupting chemicals, heavy metal ions, marine biotoxin, and other environmental contaminants. In addition, difficulties and future prospects in the development of MCOFs for environmental analysis have been examined.

Microplastics (MP) have become the major (or most important contributor) to the pollution of the environment in the recent decades. Millions of tonnes of plastic litter are transported into the marine environment annually, and these quantities are expected to increase continuously in the coming years. Monitoring of MPs in beach sand and sediment provides the information on extent of MPs pollution in the ocean, and also indicates consumption pattern of plastic at local, regional and global scale. This comprehensive review focuses on beach sand and sediment sampling, along with processes and methods for identification and quantification of MPs in these environmental media. Major analytical techniques for characterisation of MPs such as Fluorescence Microscopy, Fourier Transform IR spectroscopy (FTIR), Thermogravimetric Analysis (TGA), Chromatographic techniques (GC-MS/ HPLC), and Scanning Electron Microscopy (SEM) have been discussed in depth with respect to the analysis of beach sand and sediment samples. This review also provides a snapshot of environmental distribution of MPs in beach sand and sediments with respect to recent studies across the globe since 2017 and the challenges and future directives in the research area of MPs.

Environmental pollution is a serious problem that affects millions of people, and the demand for frequent quality monitoring is increasing. As a result, it has proven difficult to provide analytical platforms that combine high sensitivity, selectivity, and accuracy while maintaining low cost, portability, and user-friendliness. Electrochemical paper-based analytical devices (ePADs) are powerful analytical platforms that can satisfy these requirements. Paper is a superior substrate for electrochemical analysis due to its non-reactive backdrop, compatibility with both aqueous and non-aqueous analyses, and the capacity to quickly obtain a sophisticated device with high sensitivity and functionality in just a few steps. In this review, the focus is on the most recent applications of ePADs for the assessment of pollutants published in the past five years. ePADs are used for the sensitive and selective analysis of pollutants in different environmental matrices. Furthermore, the effects of nanomaterials on the fabrication of electrodes on paper-based substrates as well as on the sensitivity of electrochemical measurements, are discussed in this review. Finally, the possibility of using these ePADs in industrial and commercial applications is discussed from the authors’ point of view.

Due to its crucial importance in many industries, such as food, agrochemicals, and pharmaceuticals, chirality has gained increasing attention in recent decades. To address the need for a pure enantiomer, several methods have been developed such as crystallization, chromatographic approaches, kinetic resolution enzymatic methods, microbiological methods, and extraction. This review provides an overview of enantioselective extraction methods as being flexible, cost-effective, and suitable for large-scale production. Solid-liquid extraction (SLE) and liquid-liquid extraction (LLE) are the most used chiral extraction methods, showing significant benefits and leading to the widespread application of the method at large scale for industrial purposes. Several novel methods have been developed over the last few years to perform LLE and SLE, however, the traditional methods are still widely utilized. Throughout the paper monophasic recognition chiral extraction, biphasic recognition chiral extraction, and multi-stage LLE techniques, as well as the magnetic, molecularly imprinted polymer, metal-organic frameworks-based SLE methods are discussed as the most frequently used methods in the context of both benefits and limitations. Although there have been several publications on enantioselective LLE and SLE, no comprehensive review has been reported during the past few years. In this study, different categories and applications of both techniques have been considered.

Environmental pollution is the main threatening factor to human health, survival and global sustainable development. Achieving rapid, sensitive detection of contaminants is extremely important for timely environmental pollution monitoring and treatment. Quantum dot (QD) probes have become a common method for the detection of contaminants. In particular, the development of QDs based on nonmetallic element-doped carbon materials QDs and other nonmetallic doped Si QDs, MoOx QDs, MoS₂ QDs, and MXene QDs provides a more convenient and effective means of detecting pollutants. However, a comprehensive summary of the application of nonmetal-doped QD probes for contaminant detection is still lacking. To address this issue, in the present work we mainly categorize different nonmetal-doped QDs into “top-down” and “bottom-up” strategies based on their preparation methods. QD probes based on nonmetal doping have unique optical properties, such as a narrow excitation spectrum, optical tunability, high fluorescence quantum yield (QY), and fluorescence stability. Fluorescence sensing technology can be realized through sensing mechanisms such as fluorescence/dynamic quenching, photoinduced electron transfer (PET), internal filtering effect (IFE), and fluorescence resonance energy transfer (FRET). Considering the ease of implementation, operation, and immediate response of fluorescence sensing technology, it has been widely used in research for the detection of environmental pollutants. We have found that fluorescence sensing technology based on nonmetal-doped QD probes can achieve rapid detection of pollutants (such as heavy metals in water or food, harmful nonmetallic ions, organic pesticides, and antibiotic residues), and its limit of detection (LOD) can reach the picomolar level for trace detection. In addition, the fluorescence sensing technology of nonmetallic QD probes can be combined with smart devices to realize real-time monitoring of pollutants. Our work provides additional strategies for developing nonmetal-doped QD probe-based detection of contaminants and advancing future environmental governance.

Per- and polyfluoroalkyl substances (PFAS) are a large group of more than 4700 individual compounds which are applied in a wide range of applications in industrial processes and consumer products due to their water and oil repellency and surfactant properties. Concerns on PFAS arise from the very high stability, bioaccumulation potential and toxicity and the ubiquitous occurrence in humans, animals, soils, sediments, surface, ground and drinking waters. Advanced analytical methods are needed to investigate the input and fate of PFAS and potential transformation products in the environment and the exposure pathways for humans and wildlife. Therefore, nontarget screening (NTS) methods by high-resolution mass spectrometry (HRMS) coupled to chromatography are often applied to meet the analytical challenges arising from the high number and chemical diversity of individual compounds, the lack of authentic standards and information on identity and application areas. In this critical review we discuss the recent advances of NTS workflows applied to detect and identify PFAS based on the intrinsic information contained in data from chromatography and HRMS data on the MS¹ and MS² level. This includes retention time and peak shape characteristics, data on accurate mass and isotopologues, and high-resolution mass fragments. Successful approaches for prioritization and identification of PFAS are mostly based on mass defect filtering, Kendrick mass defect analysis, mass matches with suspect lists, assignment of chemical formulas, mass fragmentation patterns, diagnostic fragments and fragment mass differences. So far NTS approaches for PFAS were able to identify more than 750 compounds. However, still limited applicability of chromatography and ionization methods and limited mass resolving power and accuracy largely restrict a complete identification of a high number of unknown PFAS in complex samples from environmental compartments and biota.