Showing papers in "Trends in Analytical Chemistry in 2018"

Microplastics in soils: Analytical methods, pollution characteristics and ecological risks

Abstract: Microplastics are emerging persistent contaminants of increasing concern. Although microplastics have been extensively detected in aquatic environments, their occurrence in soil ecosystems remains largely unexplored. This review focused on recent progress in analytical methods, pollution characteristics and ecological effects of microplastics in soils. In spite of the presence of microplastics in soils, no standardized methods are available for the quantification. Uniform protocols including microplastic extraction and identification are urgently needed to develop. In soil environments, main sources of microplastics include mulching film, sludge, wastewater irrigation and atmospheric deposition. The fate of microplastics is closely related to soil physio-chemistry and biota. Existing evidence shows that microplastics can influence soil biota at different trophic levels, and even threaten human health through food chains. Therefore, further research is needed to fully reveal the fate and ecological risks of microplastics in soils; and necessary action is required to control microplastic pollution in terrestrial ecosystems.

Future challenges on the use of blockchain for food traceability analysis

Abstract: The steady increase in food falsification, which has caused large economic losses and eroded consumers’ trust, has become a pressing issue for producers, researchers, governments, consumers and other stakeholders Tracking and authenticating the food supply chain to understand provenance is critical with a view to identifying and addressing sources of contamination in the food supply chain worldwide One way of solving traceability issues and ensuring transparency is by using blockchain technology to store data from chemical analysis in chronological order so that they are impossible to manipulate afterwards This review examines the potential of blockchain technology for assuring traceability and authenticity in the food supply chain It can be considered a true innovation and relevant approach to assure the quality of the third step of the analytical processes: data acquisition and management

Nanozyme: An emerging alternative to natural enzyme for biosensing and immunoassay

Abstract: Nanozyme, a term defined for nanomaterial with enzyme-like properties, has attracted significant research attention owing to its striking merits. Recently, a surge of nanozymes have been demonstrated to catalyze some typical enzymatic reactions mimicking oxidase, peroxidase and catalase. Especially, nanozymes with peroxidase-like activity have grown into a big family due to their broad range of applications in the field of biosensing and immunoassay. Since inorganic nanoparticles possess the advantages of high stability and easy surface modification, nanozymes have been emerging alternatives to natural enzymes to some extent. In this Review, we briefly summarize several typical nanozymes and then focus our attention on their enormous applications with respect to analytical chemistry. Representative examples would be discussed in detail from the literatures of last 10 years. Additionally, the current challenges and future directions about nanozymes are speculated at the end of this review.

Recombinase polymerase amplification: Basics, applications and recent advances.

Abstract: Recombinase polymerase amplification (RPA) is a highly sensitive and selective isothermal amplification technique, operating at 37–42°C, with minimal sample preparation and capable of amplifying as low as 1–10 DNA target copies in less than 20 min. It has been used to amplify diverse targets, including RNA, miRNA, ssDNA and dsDNA from a wide variety of organisms and samples. An ever increasing number of publications detailing the use of RPA are appearing and amplification has been carried out in solution phase, solid phase as well as in a bridge amplification format. Furthermore, RPA has been successfully integrated with different detection strategies, from end-point lateral flow strips to real-time fluorescent detection amongst others. This review focuses on the different methodologies and advances related to RPA technology, as well as highlighting some of the advantages and drawbacks of the technique.

MXene: An emerging material for sensing and biosensing

Abstract: MXene has emerged as an amazing family of two dimensional (2D) layered materials and drawn great attention from researchers of diverse scientific fields. MXenes are the recent advancements of materials chemistry which include early transition metal carbides, nitrides and carbonitrides produced by exfoliation of selective MAX phases. MAX phase corresponds to the general formula Mn+1AXn (n = 1, 2, 3) where M represents early d-block transition metals, A stands for main group sp elements (specifically groups 13 and 14) and X is either C or N atoms. MXenes have left a prodigious impact on scientific communities with new technological advancements for a plethora of potential applications in the field of catalysis, clean energy, electronics, fuel cells, supercapacitors etc. With high metallic conductivity, hydrophilicity, low diffusion barrier, high ion transport properties, biocompatibility, large surface area and ease of functionalization, the MXenes act as fascinating interface for designing next generation detection systems exploiting their utilization in analytical chemistry. Recent progress in the field of MXenes emphasizing their significant role in analytical sensing has been well discussed in this review. Future perspectives with a motivated research in the field of MXenes based sensors have been focused at the end. The underlying goal of this review is to acquaint the readers with the sensing applications of MXenes and to document the latest advancements made in this area till date.

Extraction techniques with deep eutectic solvents

Abstract: In last years, a plethora of extraction techniques has emerged as environmental-friendly alternatives to conventional extraction procedures. In this particular field, a novel class of solvents known as deep eutectic solvents (DES) has arisen as a new and very promising tool. Compared with conventional organic solvents, DES as well as the so-called natural deep eutectic solvents (NADES) have attracted considerable attention due to the fact that they not only are eco-friendly, non-toxic, and biodegradable organic compounds but also have a low cost, being easy to produce in the own laboratory. The present review provides a critical and organized overview of novel extraction techniques using DES as extracting solvents that were applied in food, biological and environmental sample analysis. An evaluation of how these DES/NADES could improve extraction yields of a variety of analytes and advantages and limitations of each proposal will be discussed and compared with earlier studies.

Wastewater-based epidemiology biomarkers: Past, present and future

Abstract: Wastewater is a complex matrix containing a wide range of chemical and biological markers of human activity. Relating concentrations of these "waste" materials in wastewater influent streams to population-scale use, consumption, or rates of exposure, can provide important qualitative or quantitative information on the activity of inhabitants within a given wastewater catchment. Many publications in this field of study have focussed on the usage of pharmaceuticals, illicit drugs, tobacco and alcohol. However, many other potential applications are emerging which can contribute useful knowledge on human health, exposure to industrial chemicals, infectious diseases or pathogens and antibiotic resistance. This review summarises the established wastewater based epidemiology (WBE) biomarkers, and presents a critical review of the current capabilities of WBE. We further discuss possible future strategies and challenges anticipated in analysing wastewater to measure chemical markers of population health as well as biological markers of microbial exposure and disease. (c) 2018 Elsevier B.V. All rights reserved.

Advances on methods and easy separated support materials for enzymes immobilization

Abstract: Compared with free enzymes, immobilized enzymes are more robust and resistant to environmental changes. In addition, with enhanced stability, immobilized enzymes can be separated from the reaction mixture and used for repeated cycles. These advantages prompt their applications in various fields. This review outlines the existing methods and easy separated support materials for enzymes immobilization. After a brief introduction on the immobilized enzyme, the immobilization methods of adsorption, entrapment, covalent attachment and cross-linking are discussed. The emphasis is given on the easy separated support materials of magnetic nanoparticles (MNPs), membranes and capillary columns. An outlook on the immobilized enzyme is given at last.

Review of optical sensors for pesticides

Abstract: Sensors for pesticides with high sensitivity have been urgently required to control food safety, protect ecosystem and prevent disease. In this review, we provide an overview of recent advances and new trends in optical sensors for the detection of pesticide based on fluorescence, colorimetric and surface enhanced Raman scattering, surface plasmon resonance and chemiluminescent strategies. These methods will be classified by the types of recognition elements, including enzyme, antibody, molecularly-imprinted polymers, aptamer and host-guest reaction. This review explores the basic features of established strategies through assessment of their performance. In addition, we provide brief summary of the entire review, the drawbacks of present sensor and future prospects, as well as the ongoing efforts to pesticide optical sensors.

A critical analysis of extraction techniques used for botanicals: Trends, priorities, industrial uses and optimization strategies

Abstract: Plant extracts have been long used by the traditional healers for providing health benefits and are nowadays suitable ingredient for the production of formulated health products and nutraceuticals. Traditional methods of extraction such as maceration, percolation, digestion, and preparation of decoctions and infusions are now been replaced by advanced extraction methods for increased extraction efficiency and selectivity of bioactive compounds to meet up the increasing market demand. Advanced techniques use different ways for extraction such as microwaves, ultrasound waves, supercritical fluids, enzymes, pressurized liquids, electric field, etc. These innovative extraction techniques, afford final extracts selectively rich in compounds of interest without formation of artifacts, and are often simple, fast, environment friendly and fully automated compared to existing extraction method. The present review is focused on the recent trends on the extraction of different bioactive chemical constituents depending on the nature of sample matrices and their chemical classes including anthocyanins, flavonoids, polyphenols, alkaloids, oils, etc. In addition, we review the strategies for designing extraction, selection of most suitable extraction methods, and trends of extraction methods for botanicals. Recent progress on the research based on these advanced methods of extractions and their industrial importance are also discussed in detail.

Recent advances in the construction and analytical applications of metal-organic frameworks-based nanozymes

Abstract: The nanozymes are a kind of synthetic nanomaterials with enzyme-like properties. Metal–organic frameworks (MOFs) are an important class of inorganic–organic hybrid crystals. Their unique composition, structural diversity and size tailorability enable them to be promising for the construction of novel nanozymes. This review intends to summarize the recent advance for the construction of MOFs-based nanozymes and their primary applications in chemical sensing and biosensing. Based on their synthetical strategies, the MOFs-based nanozymes are categorized into four classes: pristine MOFs, MOFs with chemical modification, MOFs-based composites and MOF derivatives. In each categorization, the design and enzyme mimetic activity are discussed. Moreover, the analytical applications of these nanozymes are covered, such as the detection of H2O2, small biomolecules releasing H2O2, reductive small biomolecules, biomacromolecules, heavy metal ions, toxic metabolite of fungi, antibiotics, and so on. Finally, a summary and future perspective on the applications of MOFs-based nanozymes are briefly discussed.

Review of nanomaterials as sorbents in solid-phase extraction for environmental samples

Abstract: Anthropogenic organic contaminants (AOCs) are found to exert significant impacts on the human ecosystem, even at low or trace-level concentrations. To meet the growing demand for their quantitation in diverse environmental media, the use of preconcentration approaches (such as solid phase extraction) has become an essential component to practically upgrade both procedural efficiency and the analytical sensitivity. Nanomaterials (NMs) are realized as excellent candidates for proper sorption media because of their unique structural and surface properties with noticeably enhanced sorption capability towards contaminants. This review explores the use of various NMs (metallic and mixed oxide nanoparticles (NPs), carbon NMs (fullerenes, carbon nanotubes, graphene, and graphene oxide), polymer-based nanocomposites (organic polymers, inorganic and hybrid polymers, molecularly imprinted polymers, and dendrimers), and silicon/magnetic NPs) as potential sorbents for analytical applications. In this review, the distinctive features of NM-based sorptive extraction techniques are examined comprehensively with the discussion on their future prospects and key challenges.

Recent advances in graphene-based magnetic composites for magnetic solid-phase extraction

Abstract: In recent years, graphene-based magnetic composites have attracted tremendous research interest owing to its exceptional properties, such as huge surface area, large delocalized π-electron system, strong magnetic responsiveness, and excellent mechanical/thermal stability. These promising properties together with the ease of processibility and functionalization render graphene-based magnetic composites to be ideal adsorbents in magnetic solid-phase extraction. In this review, we outline the state of the art on the preparation approaches for different graphene-based magnetic composites and its application as adsorbents in preconcentrating organic compounds, biological macromolecules, and metal ions. In addition, future research directions of this type of magnetic materials are identified as well.

Literature update of analytical methods for biogenic amines determination in food and beverages

Abstract: Biogenic amines (BAs) have been reported in a variety of foods, such as fish, meat, cheese, and wines. The formation of BAs in food by the microbial decarboxylation of amino acids can result in human allergic reactions, characterized by difficulty in breathing, rash, vomiting, and hypertension. Control measures to prevent biogenic amine formation in foods and/or reduce their levels should be considered. Therefore, monitoring of BAs in food samples with the application of analytical techniques is of high importance. This review is based on literature data from 2010 until today and refers to food samples and alcoholic beverages. The rationale of this study is to provide data for the occurrence of BAs in food and beverages samples and a comparison of the analytical techniques and challenges in liquid and solid matrices. Importantly, BAs can be used as future markers for quality and freshness of the food products and alcoholic beverages.

Nanomaterials-based electrochemical detection of heavy metals in water: Current status, challenges and future direction

Abstract: The existence of heavy metals in the natural waters poses serious threats to human health and the environment. Therefore, development of detection methods for monitoring of these heavy metals is crucial. The nanomaterial-based electrochemical sensors have been extensively employed for heavy metal ions detection. The fabricated electrodes offer several advantages and improved performance due to the design of electrode surface at the nanoscale that render increased catalytic activity and conductivity, active large surface area and fast electrode kinetics. Moreover, integration of electrochemical devices in automatic fluidic structures has also been used for a wide range of heavy metals monitoring. This review will provide a detailed account of recent progress in the development of nanomaterial-based electrochemical sensors for the detection of heavy metals in real water samples from 2013 onwards. The design of these sensors is based on the deployment of nanoparticles-modified electrodes, microelectrode and nanoelectrode arrays, and microfluidic electrochemical devices.

Detection methods and applications of microfluidic paper-based analytical devices

Abstract: This review reports on recent advances in state-of-the-art detection methods for microfluidic paper-based analytical devices (μPADs). The review commences by describing the materials, fabrication methods and driving mechanisms employed in μPADs. The review then explores the main detection methods and applications of μPADs proposed over the past five years. The discussions focus on seven detection technologies, namely (1) colorimetric detection, (2) fluorescent detection, (3) electrochemical detection and photoelectrochemical detection, (4) chemiluminescent detection, (5) electrochemiluminescent detection, (6) nanoparticle-based detection, and (7) spectrometry detection. Overall, the review provides a useful insight into recent advances in the μPAD detection field and serves as a useful source of reference for further research and innovation in the field.

Nanomaterial-based optical chemical sensors for the detection of heavy metals in water: Recent advances and challenges

Abstract: The anthropogenic release of heavy metals into the natural water has become a global epidemic. Heavy metal contamination poses serious threats to human health and the environment. Therefore, the development of sensors for monitoring of these toxic metals in different matrices, especially in water, is very important. As a powerful analytical tool, nanomaterial-based chemical sensors have been extensively employed for the detection of heavy metals. These nanosensors offer several advantages including high sensitivity, selectivity, portability, on-site detection ability and improved performance of devices. Moreover, the deployment of molecular recognition probe on the nanostructures for the selective binding have enhanced the selectivity and detection ability. In this review, we critically engross on the recent progress in the design of nanomaterial-based sensors for the detection of heavy metals using various sensing strategies. The optical sensors focused and discussed in the review include fluorescent, surface enhanced Raman scattering and surface plasmon resonance sensors.

Recent advances in sensors for tetracycline antibiotics and their applications

Abstract: To control food safety, protect human safety and health, sensors for tetracycline antibiotics with easy operation, in-situ applications, high sensitivity and selectivity have been urgently needed. In this review, we provide an overview of recent advances and new trends in sensors for the detection of tetracycline antibiotics based on optical sensors, electrochemical sensors and other sensors including electrochemiluminescence and photoelectrochemical strategy. And we pay more attention to the practical applications of sensors for tetracycline antibiotics. Furthermore, a brief summary of the entire review, compare detection methods for different applications in the area of quantitative detection of tetracycline antibiotics, along with discussing the drawbacks of present sensors are concluded. Finally, the current challenges, ongoing efforts and future prospects in this field are also included to provide an overview for future research directions.

Investigation of microplastics in aquatic environments: An overview of the methods used, from field sampling to laboratory analysis

Abstract: Microplastics pollution in aquatic ecosystems has aroused increasing global concern, leading to an explosive growth of studies regarding microplastics published in the past few years. To date, there is still a lack of standardized methodologies used for the detection of microplastics within environmental samples, thus hampering comparison of the reported data. This review summarizes the currently used methodologies for sampling, extracting and identifying microplastics in three kinds of aquatic environmental matrices (water, sediment and aquatic biota) and includes a critical discussion of the advantages and limitations of these methodologies. The quality control and quality assurance measures taken to reduce background contamination and validate analytical methods are also discussed. Finally, this review highlights the current challenges and gives suggestions for the future research.

Aptamer-based assays and aptasensors for detection of pathogenic bacteria in food samples

Abstract: Due to increased concerns about food safety, rapid, specific and highly sensitive monitoring of pathogen bacteria in food samples is of great importance to ensure public health. Although traditional detection methods are available, they are time consuming, labor intensive, unsuitable for on-site detection, and need highly trained personnel. To overcome these limitations, many efforts have been devoted to develop a new class of bioassays, aptamer-based assays, which use nucleic acid as bio-recognition elements. Aptamer-based assays and aptasensors, as emerging analytical methods, have opened new horizons for simple, specific and sensitive detection of microorganisms including pathogen bacteria. This review therefore will focus on new developed aptamer-based assays and aptasensors for pathogenic bacteria in food samples. We will also highlight advantages and drawbacks of various types of assays developed for pathogen bacteria detection.

Bioanalytical methods for hypochlorous acid detection: recent advances and challenges

Abstract: Hypochlorous acid (HOCl), a well-known universal disinfectant in clinical practice, plays important roles in immune systems of animal and human bodies. For understanding the roles of HOCl in living systems, a number of approaches, including chemiluminescence, colorimetric, electrochemical and chromatographic methods have been explored. For the detection of HOCl in live organisms, cutting-edge techniques, such as fluorescence/phosphorescence molecular probes, responsive nanoprobes, Raman and activatable photoacoustic sensors, have also been developed recently. In this review, the recent advances in the development of bioanalytical methods for detection of HOCl in environmental and biological specimens were summarized. More specifically, traditional techniques for assay of HOCl in bulk solution were initially discussed, and then fluorescence molecular probes, phosphorescence probes, responsive nanoprobes and other methods for HOCl detection were reviewed, which gives an overview of the developments and applications in bioanalytical methods for HOCl detection.

Advancement and prospects of bioinformatics analysis for studying bioactive peptides from food-derived protein: Sequence, structure, and functions

Abstract: Food-derived bioactive peptides, as potential ingredients in health-promoting functional foods targeting diet-related chronic diseases, have attracted increasing attention because of their high biological activities, low toxicity, and easy of metabolism in human body. However, conventional methods for analyzing the bioactive peptides are not only expensive but also time-consuming; these drawbacks limited detailed studies and rapid development of bioactive peptides. Emerging bioinformatics approaches may overcome these problems to enable bioactive peptide research. The aim of this review is to provide an overview of research progress in the bioinformatics methods used for identifying, characterizing, elaborating bioactive mechanisms of, and producing food-derived bioactive peptides, and also to present an effective workflow. The workflow has been integrated in silico and traditional methods to predict, validate, and modify bioactive peptides.

Raman microspectroscopy as a tool for microplastic particle analysis

Abstract: This review discusses the identification and quantification of microplastic (MP) using Raman microspectroscopy (RM). It addresses scientists investigating MP in environmental and food samples. We show the benefits and limitations of RM from a technical point of view (sensitivity, smallest particle sizes, speed optimizations, analysis artefacts and background effects) and provide an assessment of the relevance of lab analyses and their interpretation (sample sizes for the analysis, uncertainty of the analysis). All parts are complimented by extensive literature data and a theoretical derivation of the concepts. We conclude with suggestions for a feasible and meaningful RM analysis of MP samples.

Metal ions doped carbon quantum dots: Synthesis, physicochemical properties, and their applications

Abstract: As an efficient method to improve the intrinsic properties of carbon quantum dots (CQDs), doping CQDs with heteroatoms including nonmetallic atoms and metal ions recently receive great attention. Since the summary about the achievements of CQDs doping with nonmetallic atoms has been carried out. In this minireview, we will overview the state-of-the-art knowledge of metal ions doped-CQDs (M-CQDs). The synthetic routes for M-CQDs, the novel physicochemical properties originating from their unique morphology and constitute, and their applications in environmental, biological and energy-related areas will be summarized and highlighted. The review aims to provide new insights into the exploration of the methods in order to improve the functionality of M-CQDs, the relationship between newly novel physicochemical properties and metal ions doping, as well as their possible applications in future.

Recent progress on surface chemistry of plasmonic metal nanoparticles for colorimetric assay of drugs in pharmaceutical and biological samples

Abstract: Plasmonic metal nanoparticles have been explored as a new class of chemical read-outs for assaying of a variety of chemical and biological species because of their unique physico-chemical and size dependent properties. Metal nanoparticles-based optical technologies are based on either new class of organic molecular assembly or with aggregation-induced optical changes features, which can also improve the sensitivity of drug assays in pharmaceutical analysis. This review describes the advantages of surface chemistry of plasmonic metal nanoparticles (e.g., silver, copper, gold, and platinum) for tuning of their colorimetric sensing applications in various drugs assays in pharmaceutical and biological samples. It provides insights of various plasmonic metal nanoparticles-based sensing strategies for the selective, sensitive and simultaneous colorimetric assay of drugs in pharmaceutical samples. Finally, we listed some research challenges to accelerate the development of plasmonic metal nanoparticles-based colorimetric sensors that are directly applicable for assaying drugs in pharmaceutical samples.

(Bio)Analytical chemistry enabled by 3D printing: Sensors and biosensors

Abstract: 3D printing has revolutionized the concept of object manufacturing, making an enormous impact on industry and economy. The technology has found a niche in countless fields, including scientific research. It has rendered practical solutions to scientific problems by offering tailored-shaped devices with exquisite control in design and geometry and through the versatility of printable materials. Applications in analytical and bioanalytical chemistry have been on the rise, with microfluidics being one of the most represented areas of 3D printing towards this chemistry branch. Most stages of the analytical workflow comprising sample collection, pre-treatment and readout, have been enabled by 3D-printed components. Sensor fabrication for detecting explosives and nerve agents, the construction of microfluidic platforms for pharmacokinetic profiling, bacterial separation and genotoxicity screening, the assembly of parts for an on-site equipment for nucleic acid-based detection, the manufacturing of an online device for in vivo detection of metabolites, represent just a few examples of how additive manufacturing technologies have aided the field of (bio)analytical chemistry. In this review, we summarize the most relevant trends of 3D printing applications in this field.

Recent advances in facile synthesis and applications of covalent organic framework materials as superior adsorbents in sample pretreatment

Abstract: Sample pretreatment is an essential step in analytical chemistry, especially for the analysis of organic pollutants from environmental, biological and food samples Covalent organic frameworks (COFs) are an emerging group of microporous materials Recently, COFs have attracted increasing attentions in the field of sample pretreatment due to their advantages such as high surface area, tunable pore size, good chemical selectivity and thermal stability This review outlined the diverse ways for the facile preparation of COFs, and also summarized the applications of COFs as novel sorbents for the extraction of diverse targeted analytes (such as polycyclic aromatic hydrocarbons, phenols, pyrethroids and pesticides) from complex samples In addition, the deficiencies and development prospects of COF materials for sample pretreatment in the future were also discussed This review hopefully can stimulate interdisciplinary research at the intersection of COFs and sample pretreatment

Application of molecularly imprinted polymers in analytical chiral separations and analysis

Abstract: Over the last two decades the process of development and application of a new types of molecular imprinted polymer (MIP) sorbents in the field of analytical chemistry have been widely described in the literature. One of the new trends in analytical chemistry practice is the use of new types of MIP sorbents as specific sorption materials constituting the stationary phase in advanced separation techniques. The following review paper contains comprehensive information about the application of a specific and well defined MIP sorbents (with the data base in the paper about the reagents used in MIP preparation process) as stationary phases in separation techniques including high performance liquid chromatography and capillary electrochromatography. Coverage includes newly created types of stationary phases (MIP sorbents) used for chiral recognition, with the focus on applications in enantioselective separation.

MoS2 nanostructures for electrochemical sensing of multidisciplinary targets: A review

Abstract: With the emerging interest in layered transition metal dichalcogenides (TMDs), MoS2 has occupied a unique place in recent times as graphene (GR) analog. Development of novel state of the art electrochemical approaches at MoS2 modified working surfaces is an upcoming field and holds great promise for design and development of next generation sensing devices. Large available surface area, high biocompatibility and structural versatility of 2D/3D MoS2 nanostructures have produced numerous hybrid sensors and biosensors which have demonstrated their prominent role in biological, environmental, pharmaceutical, chemical, industrial and food analysis. A comprehensive and critical detail of recent advancements of MoS2 based sensors for real time applications have been presented in the present review. Overall conclusion related to sensing performances of MoS2 nanostructures and future needs to further exploit the unusual properties of mono and few layer of other TMDs for developing advance recognition systems have been concluded at the end.

Fabrications of novel solid phase microextraction fiber coatings based on new materials for high enrichment capability

Abstract: Enrichments of emerging pollutants and drugs from various samples with complex matrices make it urgent and challenging to develop novel SPME coatings, and the flourishing materials with high enrichment capabilities provide good opportunities for it. This review summarizes the used materials for the fabrication of SPME coatings in the past five years, including carbon, polymer, metal organic frameworks (MOFs), covalent organic frameworks (COFs), ionic liquids (ILs), metal/metal oxide nanoparticles and silica. To obtain SPME coatings with excellent physical performance, anti-interference ability and high enrichment capability, suitable coating methods and supports are selected according to the properties of coating materials. In addition, the factors of coating materials and analytes influencing the enrichment effect are summarized and illustrated preliminarily, benefiting for further design of advanced coating materials with enhanced performance.