磁性固相萃取吸附剂用于富集环境和食品中残留农药的研究进展

残留农药在体内积累会影响人的健康。种类多样的残留农药广泛存在于环境和食品中,建立高效的样品前处理技术对痕量残留农药进行富集尤为重要。磁性固相萃取技术因其简单、易操作和吸附剂回收方便等优点,被广泛用于富集残留农药。本文介绍了近年来多种材料参与构建的磁性固相吸附剂在残留农药检测中的应用,并对磁性固相吸附剂的发展趋势进行了展望。     

分子印迹聚合物在极性农药残留检测中的应用进展

极性农药包括杀菌剂、除草剂、杀虫剂等,种类丰富,成本低廉,在农业中应用广泛,其滥用易导致水资源和土壤等环境污染,人类通过间接接触动植物源性食品和环境中的极性农药残留也增加了农药暴露风险。极性农药的物理化学性质差异大,通常痕量存在于食品和环境样品等复杂基质中,这对其准确检测分析带来了挑战。分子印迹聚合物(MIPs)作为一种人工制备的选择性吸附剂,具有与模板分子在空间结构、大小尺寸和功能基团上互补的特定识别位点,且易于制备,成本低,稳定性好,重复利用率高,已被广泛用于极性农药残留的样品前处理和分析检测中。MIPs可以作为固相萃取(SPE)、固相微萃取(SPME)、磁性固相萃取(MSPE)、搅拌棒固相萃取(SBSE)等前处理方法的吸附剂,还可用于制备光、电、化学传感器,作为质谱检测的离子源基底和拉曼光谱的增强基底。目前针对极性农药残留的检测,已有许多研究报道了多种分子印迹材料用于高效分离分析各种复杂基质中的极性农药残留,但未见此方面的综述报道。该文首先介绍了MIPs的印迹策略、聚合策略,并针对传统MIPs制备和应用中存在的问题,简要概括了一些新型的分子印迹策略和制备技术;然后从极性农药残留分析的角度出发,总结归纳了分子印迹材料近年来特别是近5年来在各种极性农药残留(包括新烟碱类、有机磷类、三嗪类、唑类、脲类等)检测中的应用,并针对现存问题展望了其未来的发展方向和趋势。     

磁性纳米材料的功能化及其在农药残留检测中的应用

磁固相萃取技术是近年来不断发展的一种基于磁性纳米吸附材料的新型样品前处理技术。与传统吸附剂相比,磁性纳米材料凭借其粒径小、比表面积大、表面易功能化、独特的磁学性质、易于操控和再生、环境友好度高等诸多优点,在有效分离富集复杂基质中的痕量目标物方面展示了诱人的应用前景。近年来,磁固相萃取技术在农药残留检测领域取得了迅速发展。介绍了磁固相萃取技术,综述了近5年来碳材料、有机小分子、离子液体、高分子、无机氧化物、金属有机框架材料、多孔有机材料等功能化的磁性纳米材料的合成策略、在农药残留检测中的应用以及其与分析物之间吸附机理,并展望了其发展方向。     

粮油作物及茶叶中农药多残留检测的前处理技术进展

综述了粮油作物和茶叶中农药多残留检测的前处理技术,包括超临界流体萃取、加速溶剂萃取、搅拌棒吸附萃取、分散固相萃取、固相微萃取和在线凝胶渗透色谱等样品前处理方式,并详细介绍了各种方法的原理、优点及适用范围,可为粮油作物和茶叶中农药多残留检测技术的发展提供参考。     

新型纳米材料在农产品安全分析中的应用进展

农产品质量安全事关民生福祉，近年来受到了政府和消费者越来越多的关注，建立农产品中农药、兽药、重金属和真菌毒素等污染物高效、快速和灵敏的分离分析新方法，对于保障农产品质量安全具有重要的意义。农产品基质复杂，污染物浓度低，采取适当的样品前处理对农产品中的污染物进行富集净化是非常重要的。固相萃取是目前应用最多的样品前处理技术，其核心吸附剂决定了萃取的选择性和萃取效率。近年来，越来越多的新型材料被用作固相萃取的吸附剂，结合多种萃取模式(固相微萃取、分散固相萃取、磁性固相萃取等),大大提高了目标物的萃取效率、萃取选择性和分析通量。纳米材料具有大的比表面积，对痕量目标物亲和力强，将其作为固相萃取的吸附剂，极大地改善了分析技术的选择性和灵敏度，已经成为农产品中痕量化合物预富集技术的优先选择。本文概述了磁性材料、碳基材料、金属和金属氧化物材料、金属有机骨架材料、有机共价骨架材料等纳米材料的吸附特性，因具有比表面积大、吸附容量高、结构可设计等众多优点，良好的稳定性和优异的物理化学性能使其非常适合作为农产品安全分析中污染物富集净化的吸附剂，结合色谱、光谱、质谱等检测技术，所开发的分析方法成功应用于多种农产...     

分子印迹固相萃取技术在动物源食品中药物残留检测应用进展

以分子印迹材料作为特效吸附剂的分子印迹固相萃取技术具有从复杂样品中选择性吸附目标分子及其结构类似物的能力,较好地克服了由于样品复杂所带来的内源性干扰问题,因此非常适用于复杂样品的预处理与富集。本文介绍了分子印迹固相萃取技术的原理、最新进展以及相关萃取参数的优化过程,对近几年国内外分子印迹固相萃取技术在动物源食品中药物残留检测方面的应用进行了总结;阐明了分子印迹固相萃取技术在实际应用中存在的不足,并对其未来的发展进行了展望。     

共价有机框架材料在固相萃取中的最新应用进展

固相萃取技术是一种快速简便的样品前处理技术,能够实现分析物的富集,提高分析检测的准确性和灵敏度,已被广泛应用于食品安全检测、环境污染物分析等领域。如何提高方法的灵敏度和选择性是样品前处理领域的不懈追求,其关键在于萃取材料的选择。共价有机框架(COFs)材料是一类晶态多孔聚合物,其首先经热力学控制的可逆聚合反应形成连锁单元,然后与具有一定对称性的有机小分子构筑单元连接而形成,已被广泛应用于气体吸附、催化、传感、药物输送等领域。COFs具有比表面积大、孔隙率高、稳定性好、可设计性强以及合成简单、选择性高等优点,在样品前处理领域中引起了广泛关注。目前,COFs作为一种新型固相萃取材料,已被应用于食品、环境、生物样品中不同类别污染物的萃取富集,如重金属离子、多环芳烃、苯酚、氯酚、氯苯、多溴联苯醚、雌激素、药物残留、农药残留等。采用不同单体合成的COFs对于不同类型分析物具有不同的富集效果,因此也可以通过对其进行修饰合成一种新型COFs,以达到对某种结构分析物的高效选择性富集。本文将介绍COFs的主要类型及合成方法,并重点介绍近3年来COFs作为固相萃取材料在食品、环境、生物领域方面的重要应用,...     

萃取吸附剂在非甾体抗炎药残留样品前处理中的应用进展

阿司匹林和塞来昔布等非甾体抗炎药(NSAIDs)因具有消炎和止痛等疗效被广泛应用,但其具有一定的毒副作用,会引起肠胃疾病等,因而其在环境水、生物样品和食品中的残留分析已引起重视。萃取吸附剂是决定样品前处理环节中萃取效率和选择性高低的关键。本文以萃取吸附剂类别(碳基材料、金属有机骨架、低共熔溶剂和层状双氢氧化物等)为主线,综述了采用萃取技术对环境水、生物和食品样品中的NSAIDs进行前处理,配合采用高效液相色谱联用技术等进行检测分析的最新应用实例,并对今后的萃取吸附剂的发展趋势进行了展望。     

水和食品中有机磷农药残留检测的研究进展

综述了水和食品中有机磷农药残留检测中样品的前处理方法 (包括液液萃取、固相萃取、液相微萃取、固相微萃取、拌棒吸附萃取、磁固相萃取、QuEChERS等)和测定方法(包括气相色谱法、气相色谱-质谱法、液相色谱法、液相色谱-质谱法等)的研究进展(引用文献58篇)。     

分子印迹聚合物在抗生素残留测定中的应用

抗生素的滥用及残留对生物体和环境造成极大危害,其含量低、种类多、基质复杂,通常需要进行样品前处理结合色谱分析以实现灵敏测定。分子印迹聚合物（MIPs）能选择性识别、有效富集目标分析物并消除干扰,已广泛用于抗生素的样品前处理中。该文对MIPs制备中面临的挑战进行了总结;对2016年以来抗生素MIPs的固相萃取应用进行了综述和展望,主要包括固相萃取、分散固相萃取、磁固相萃取、基质固相分散萃取、固相微萃取、搅拌棒吸附萃取。此外,该文重点介绍了抗生素MIPs的印迹新策略,如多模板、多功能单体、虚拟模板、刺激响应、亲水性印迹等。最后,该文对抗生素MIPs的制备和前处理应用进行了展望。     

A review of sample preparation methods for the pesticide residue analysis in foods

The pesticide residues in foods have received increasing attention as one of the most important food safety issues. Therefore, more strict regulations on the maximum residue limits (MRLs) for pesticides in foods have been established in many countries and health organizations, based on the sensitive and reliable analysis methods of pesticide residues. However, the analysis of pesticide residues is a continuing challenge mainly because of the small quantities of analytes as well as the large amounts of interfering substances which can be co-extracted with them, often leading to experimental errors and damage to the analytical instruments. Thus, extensive sample preparation is often required for the pesticide residue analysis for the effective extraction of the analytes and removal of the interferences. This paper focuses on reviewing the recent development in the sample preparation methods for the pesticide residue analysis in foods since 2006. The methods include: liquid-liquid extraction (LLE), supercritical-fluid extraction (SFE), pressurized-liquid extraction (PLE), microwave-assisted extraction (MAE), ultrasound-assisted extraction (UAE), gel permeation chromatography (GPC), solid-phase extraction (SPE), molecularly imprinted polymers (MIPs), matrix solid-phase dispersion (MSPD), solid-phase micro-extraction (SPME), QuEChERS, cloud point extraction (CPE) and liquid phase micro-extraction (LPME), etc. Particularly their advantages, disadvantages and future perspectives will be discussed.     

pH-dependence of pesticide adsorption by wheat-residue-derived black carbon

The potential of black carbon as an adsorbent for pesticides in soils may be strongly influenced by the properties of the adsorbent and pesticides and by the environmental conditions. This study evaluated the effect of pH on the adsorption of diuron, bromoxynil, and ametryne by a wheat (Triticum aestivum L.) residue derived black carbon (WC) as compared to a commercial activated carbon (AC). The pH drift method indicated that WC had a point of zero charge of 4.2, much lower than that of 7.8 for AC. The density of oxygen-containing surface functional groups, measured by the Boehm titration, on WC was 5.4 times higher than that on AC, resulting in a pesticide adsorption by WC being 30-50% of that by AC, due to the blockage of WC surface by the waters associated with the functional groups. A small decrease (5.5%/unit pH) in diuron adsorption by WC with increase in pH resulted from increased deprotonation of surface functional groups at higher pH values. A much larger decrease (14-21%/unit pH) in bromoxynil adsorption by WC with increase in pH resulted from the deprotonation of both the adsorbate and surface functional groups of the adsorbent. The deprotonation reduced the adsorptive interaction between bromoxynil and the neutral carbon surface and increased the electrical repulsion between the negatively charged WC surface and bromoxynil anions. Deprotonation of ametryne with increase in pH over the low pH range increased its fraction of molecular form and thus adsorption on WC by 15%/unit pH. Further increase in pH resulted in a 20%/unit pH decrease in ametryne adsorption by WC due primarily to the development of a negative charge on the surface of WC. The pH-dependent adsorption of pesticides by black carbon may significantly influence their environmental fate in soils.     

Synthesis and surface engineering of magnetic nanoparticles for environmental cleanup and pesticide residue analysis: A review

In recent years, water pollution and pesticide accumulation in the food chain have become a serious environmental and health hazard problem. Direct determination of these contaminants is a difficult task due to their low concentration level and the matrix interferences. Therefore, an efficient separation and preconcentration procedure is often required prior to the analysis. With the advancement in nanotechnology, various types of magnetic core–shell nanoparticles have successfully been synthesized and received considerable attention as sorbents for decontamination of diverse matrices. Magnetic core–shell nanoparticles with surface modifications have the advantages of large surface‐area‐to‐volume ratio, high number of surface active sites, no secondary pollutant, and high magnetic properties. Due to their physicochemical properties, surface‐modified magnetic core–shell nanoparticles exhibit high adsorption efficiency, high rate of removal of contaminants, and easy as well as rapid separation of adsorbent from solution via external magnetic field. Such facile separation is essential to improve the operation efficiency. In addition, reuse of nanoparticles would substantially reduce the treatment cost. In this review article, we have attempted to summarize recent studies that address the preconcentration methods of pesticide residue analysis and removal of toxic contaminants from aquatic systems using magnetic core–shell nanoparticles as adsorbents.     

生物质炭的制备、改性以及在挥发性有机物吸附方面的应用

挥发性有机物（VOCs）是大气中重要的污染源之一,对环境和人类健康产生严重的危害。吸附法是工业中最常用的去除VOCs的方法,吸附剂是吸附技术的关键,生物质炭是一种由生物质基材料在高温下热解活化等工艺制得的炭材料,具有较高的比表面积、丰富的孔隙结构和化学活性表面,在环境污染控制领域具有广泛应用。基于最近的研究,本文系统地综述了常用于去除VOCs的生物质炭的制备和改性方法,以及生物质炭在吸附VOCs的应用研究。本文首要目标是评估生物质炭去除VOCs的能力,特别是经过各种改性和活化工艺后,评价生物质炭作为吸附剂去除VOCs的适用性;确定改性和活化后对VOCs吸附能力的影响;揭示生物质炭对VOCs可能存在的吸附机理。最后,文章也对生物质炭的再生提出了建议和展望。     

Application of Compound-Specific Isotope Analysis in Environmental Forensic and Strategic Management Avenue for Pesticide Residues

Unintended pesticide pollution in soil, crops, and adjacent environments has caused several issues for both pesticide users and consumers. For users, pesticides utilized should provide higher yield and lower persistence while considering both the environment and agricultural products. Most people are concerned that agricultural products expose humans to pesticides accumulating in vegetation. Thus, many countries have guidelines for assessing and managing pesticide pollution, for farming in diverse environments, as all life forms in soil are untargeted to these pesticides. The stable isotope approach has been a useful technique to find the source of organic matter in studies relating to aquatic ecology and environmental sciences since the 1980s. In this study, we discuss commonly used analytical methods using liquid and gas chromatography coupled with isotopic ratio mass spectrometry, as well as the advanced compound-specific isotope analysis (CSIA). CSIA applications are discussed for tracing organic pollutants and understanding chemical reactions (mechanisms) in natural environments. It shows great applicability for the issues on unintended pesticide pollution in several environments with the progress history of isotope application in agricultural and environmental studies. We also suggest future study directions based on the forensic applications of stable isotope analysis to trace pesticides in the environment and crops.     

Health risk assessment of neonicotinoid insecticide residues in pistachio using a QuEChERS-based method in combination with HPLC-UV

There is an increasing need to address the potential risks arising from combined exposures to multiple residues from pesticides in the diet. Pesticide residue-related pollution is a problem that arises because of the increased use of pesticides in agriculture to meet the growing demands of food production. In this study, pesticide residue data were obtained based on an optimized extraction method. For this purpose, we established a method based on qu ick, e asy, ch eap, e ffective, r ugged, and s afe (QuEChERS) extraction for simultaneous determination of imidacloprid (IMI) and acetamiprid (ACT) in pistachio nuts. The parameters influencing the QuEChERS method were the sample-to-water ratio and adsorbent amounts. As a result, both were optimized to improve the recovery of the analytes as well as the clean-up efficiency of the pistachio matrix. Our results indicated that a freeze-out step and use of primary and secondary amines as an adsorbent led to much cleaner chromatograms with lower baseline drift, without using graphitized carbon black and C₁₈-based adsorbent, which reduced both cost and time of analysis. Following extraction, the pesticide residues were separated and quantified by reverse-phase HPLC. For validation purposes, recovery studies were carried out using a concentration range from 20 to 2500 μg/L at nine levels. The suitable linearity, precision, and accuracy were obtained with HPLC–UV with recoveries of 70.37%–89.80% for IMI and 81.05%–113.57% for ACT, with relative standard deviations <12%. The validated method was successfully applied to the analysis of pistachio samples collected from a field trial to estimate maximum residue limits. There was no significant health risk for consumers via pistachio consumption.     

Pesticide Multi-Residue Analysis in Tea Using d-SPE Sample Cleanup with Graphene Mixed with Primary Secondary Amine and Graphitized Carbon Black Prior to LC–MS/MS

Graphene is a novel class of carbon nanostructures with ultrahigh specific surface area. Graphene has already been used in many fields and has great promise for use in sorbent materials. In this study, we used graphene mixed with primary secondary amine (PSA) and graphitized carbon black (GCB) as dispersive solid-phase extraction materials for the cleanup of tea for the first time. Compared to the literature, the amount of PSA and GCB was greatly reduced. A multi-residue method combined with liquid chromatography–tandem mass spectrometry was validated for rapid determination of 25 pesticide residues in tea. Green tea, black tea, and white tea were selected as matrixes, representing the majority of tea types. Recoveries ranged from 71.1 to 108.3 % and consistent relative standard deviations <13.6 % for all 25 pesticides. Graphene has significant potential as a promising new adsorbent for pesticide residue analysis of teas. This method can be used to analyze tea samples with different degrees of fermentation.     

Analysis of Organophosphorus Pesticides in Water with Enzyme Membrane Extraction-Gas Chromatography

The pollution of organophosphorus pesticides in water, especially in drinking water source, is a vital threat to life. Therefore, great concern is being focused on the effects of pesticide residues on public health and wildlife. The detection of trace organophosphorus pesticide residues in water is a very important task. In the recent years, the immunoassay technique has been utilized in the determination of trace organophosphorus pesticide residues in various environmental samples.     

Assessment of Primary and Secondary Amine Adsorbents and Elution Solvents with or without Graphitized Carbon for the SPE Clean-Up of Food Extracts in Pesticide Residue Analysis

Primary and secondary amine (PSA) is one of the most powerful solid-phase extraction adsorbent for clean-up of food matrices and multi-pesticide residue analysis. The present study investigates the influence of elution protocols on the capacity of PSA for removal of fatty acids and the root regarding poor recoveries of metamidophos and acephate. The uses of toluene, hexane and/or acetone in the elution severely reduce the capacity of PSA for removal of fatty acids. Water is essential in the elution for full recoveries of the polar pesticides. PSA cartridge alone, PSA/carbon serial cartridge design and the novel elution protocols have been developed for this kind of applications.