Research progress on pesticide residue detection based on microfluidic technology

The problem of pesticide residue contamination has attracted widespread attention and poses a risk to human health. The current traditional pesticide residue detection methods have difficulty meeting rapid and diverse field screening requirements. Microfluidic technology integrates functions from sample preparation to detection, showing great potential for quick and accurate high-throughput detection of pesticide residues. This paper reviews the latest research progress on microfluidic technology for pesticide residue detection. First, the commonly used microfluidic materials are summarized, including silicon, glass, paper, polydimethylsiloxane, and polymethyl methacrylate. We evaluated their advantages and disadvantages in pesticide residue detection applications. Second, the current pesticide residue detection technology based on microfluidics and its application to real samples are summarized. Finally, we discuss this technology's present challenges and future research directions. This study is expected to provide a reference for the future development of microfluidic technology for pesticide residue detection.     

Droplet-based microfluidics for dose–response assay of enzyme inhibitors by electrochemical method

A simple but robust droplet-based microfluidic system was developed for dose–response enzyme inhibition assay by combining concentration gradient generation method with electrochemical detection method. A slotted-vials array and a tapered tip capillary were used for reagents introduction and concentration gradient generation, and a polydimethylsiloxane (PDMS) microfluidic chip integrated with microelectrodes was used for droplet generation and electrochemical detection. Effects of oil flow rate and surfactant on electrochemical sensing were investigated. This system was validated by measuring dose–response curves of three types of acetylcholinesterase (AChE) inhibitors, including carbamate pesticide, organophosphorus pesticide, and therapeutic drugs regulating Alzheimer's disease. Carbaryl, chlorpyrifos, and tacrine were used as model analytes, respectively, and their IC₅₀ (half maximal inhibitory concentration) values were determined. A whole enzyme inhibition assay was completed in 6 min, and the total consumption of reagents was less than 5 μL. This microfluidic system is applicable to many biochemical reactions, such as drug screening and kinetic studies, as long as one of the reactants or products is electrochemically active.     

用于测量农药残留的小麦酯酶的选择

为研制探测农药残留的生物传感器，研究了农药乐果[O,O-二甲基S－（N－甲基胺基甲酰甲戎）二硫代磷酸酯]对各种小麦植物酯酶的抑制，从小麦中提取植物酶，以农药乐果为抑制剂，采用分光光度法研究了乐果对各种小麦酯酶活性的影响；研究显示，不同品种小麦酯酶对农药乐果的敏感度不同，在所研究的品种中，豫麦39和小麦周9对乐果较敏感，研究结果说明了选择小麦酶源的必要性。     

串联质谱法在农药残留分析中的应用

农药残留问题已经成为全球关注的热点问题,尤其是农产品和食品中的农药残留更受到各国政府和公众的普遍关注。快速、准确、灵敏的农药残留分析和检测技术已经成为保障食品安全的有效手段,是当前农药残留分析研究和发展的方向。1983年,McLafferty等发明了串联质谱技术(MS-MS),目前已发展成为一种成熟的技术,在许多研究领域发挥了巨大作用。同样,在农药残留分析领域,串联质谱技术也越来越体现出其定性准确、排除干扰能力强以及灵敏度高的特点。     

桃中农药残留分析及膳食暴露评估研究

为明确并量化食用桃途径的农药膳食摄入风险水平,通过对19个桃主产区采集的98份样品进行农药残留检测,对桃中的农药残留急/慢性膳食摄入风险进行评估,并借鉴英国兽药残留委员会兽药残留风险排序矩阵进行农药和样品风险排序。结果在桃中检出了38种农药残留,98个样品的检出率为95.9%,检出的农药含量为0.007 4～3.399 3 mg/kg;检出农药的慢性膳食摄入风险(%ADI)和急性膳食摄入风险(%ARfD)的平均值分别为0.89%和11.09%,风险均低于100%,不会对人体产生慢性或急性风险;风险排序结果表明桃果品中氟虫腈、硫丹、灭多威、丁硫克百威、毒死蜱、联苯菊酯为6种为高风险农药,应在生产和质量安全监管中予以重点关注。该文为桃安全消费、农药残留监管和农药最大残留限量(MRLs)制修订提供了科学依据。     

Current development of microfluidic immunosensing approaches for mycotoxin detection via capillary electromigration and lateral flow technology

Mycotoxin contamination in the food chain has caused serious health issues in humans and animals. Thus, a rapid on-site and lab-independent detection method for mycotoxins, such as aflatoxins (AFTs), is desirable. Microfluidic chip based immunosensor technology is one of the most promising methods for fast mycotoxin assays. In this review, we cover the major microfluidic immunosensors used for mycotoxin analysis, via flow-through (capillary electromigration) and lateral flow technology. Sample preparation from different matrices of agricultural products and foodstuffs is summarized. The choice of materials, fabrication strategies, and detection methods for microfluidic immunosensors are further discussed in detail. The sensors application in mycotoxin determination is also outlined. Finally, future challenges and opportunities are discussed.     

微流控芯片液滴生成与检测技术研究进展

微流控芯片液滴技术是一种操控微小体积液体的新技术,既可实现高通量微观样本的生成及控制,也可进行独立液滴的操作.分散的微液滴单元可作为理想的微反应器,在生物医药中的药物筛选、材料筛选和高附加值微颗粒材料合成领域展现出巨大的应用潜力.液滴微流控芯片是利用流体剪切力的改变,使互不相溶的两相流体在其界面处生成稳定、有序的液滴,...     

微流控技术在外泌体分离分析中的研究进展

外泌体是一类由细胞分泌的含有脂质、蛋白、核酸等多种物质的纳米级囊泡,主要参与细胞间的物质交换及信息传导,与多种疾病的发生发展密切相关。对外泌体进行深入研究,理解其生物学功能,对疾病诊断与治疗具有重要意义。由于外泌体尺寸较小且密度和体液接近,想要对复杂生物样本中的外泌体进行分离与分析十分困难。传统的外泌体分离方法如超速离心、超滤等大都需要借助大型仪器设备,且耗时长、操作复杂。因此迫切需要开发高效、便捷的外泌体分离检测手段。微流控技术因其微型化、高通量、可集成等特点,为外泌体的分离分析提供了一个新的平台。该文主要对近年来微流控技术在外泌体分离分析相关领域的研究进展进行了综述。重点从外泌体物理特性和生化特性两个角度出发,介绍了微流控芯片技术用于外泌体分离领域的主要原理、策略和方法。此外,还介绍了微流控技术与荧光、电化学传感、表面等离子体共振等多模态检测方法结合,实现外泌体一体化分析的新进展。最后,该文分析了目前微流控技术用于外泌体分离检测存在的挑战,并对其发展趋势和前景进行了展望。随着微流控外泌体分离分析装置的不断微型化、集成化、自动化,微流控芯片技术将在外泌体分离、生化检测、机制研究等方面将发挥越来越重要的作用。     

气相色谱法测定蔬菜中有机磷农药的残留量

采用DB-1型毛细管柱及氮磷检测器，建立了同时测定蔬菜中有机磷农药甲胺磷、氧化乐果、甲拌磷、甲基对硫磷残留量的气相色谱法，测定4种有机磷农药残留量的线性范围均为0．02-4．00mg／L，相关系数为0．9955～0.9980，检出限为0.0012～0．0020mg／L，加标回收率为89．3％-92．2％，相对标准偏差为2．2％～3．2％。     

有机磷类农药残留检测技术的应用

作为一类高效、广谱的杀虫剂,有机磷类农药被广泛用于农作物病虫防治领域,但它产生的危害也不容忽视。论述了近年来国内外有机磷类农药检测技术的应用,比较各种方法的优缺点,为农药残留检测的应用提供了参考。     

Digital droplet immunoassay based on a microfluidic chip with magnetic beads for the detection of prostate-specific antigen

Sensitive biomarker detection techniques are beneficial for both disease diagnosis and postoperative examinations. In this study, we report an integrated microfluidic chip designed for the immunodetection of prostate-specific antigens (PSAs). The microfluidic chip is based on the three-dimensional structure of quartz capillaries. The outlet channel extends to 1.8 cm, effectively facilitating the generation of uniform droplets ranging in size from 3 to 50 μm. Furthermore, we successfully immobilized the captured antibodies onto the surface of magnetic beads using an activator, and we constructed an immunosandwich complex by employing biotinylated antibodies. A key feature of this microfluidic chip is its integration of microfluidic droplet technology advantages, such as high-throughput parallelism, enzymatic signal amplification, and small droplet size. This integration results in an exceptionally sensitive PSA detection capability, with the detection limit reduced to 7.00 ± 0.62 pg/mL.     

Rapid detection of pesticide residues in Chinese herbal medicines by molecularly imprinted membrane electrospray ionization mass spectrometry

Chinese herbal medicines(CHMs) play an increasingly important role in the field of medicine and affects public health in the world.Although more and more strict has been employed to ensure the quality and safety of CHMs,pesticide residues in CHMs remain a serious issue and are the bottleneck for the global development of CHMs.In this work,we applied molecularly imprinted membrane electrospray mass spectrometry(MIM-ESI MS) for rapid detecting 4 classes of pesticide residues in CHMs,including organophosphorus(OPP),carbamates,pyrethroids and neonicotinoids in CHMs.Compared with our previous ambient ionization method MESI,MIM-ESI is capable of achieving a ～50-fold increase in the detection limit of conventional analytical methods owing to the specificity recognition and unique enrichment of MIM.The optimal experimental conditions were determined,and the method was further validated for its sensitivity and specificity.Our data showed that MIM-ESI MS is applicable for the direct quantitation of pesticide residues in CHMs.This detection technology may help to ensure the quality of CHMs in the future.     

超声波辅助萃取-气相色谱法同时测定蔬菜中5种有机磷农药残留

建立超声波辅助萃取-气相色谱法同时分离测定蔬菜中5种有机磷农药残留量的：弓．法。实验结果表明,采用超声波加速提取有机磷农药残留,样品提取效果好,干扰物少,检测快速;在DB-1701色谱柱中,供试的5种有机磷农药分离良好;以FPD为检测器,选择性较好。方法的检出限为0．004-0．01μg／mL,5种农药在2个添加水平下的回收率为78．9％-105．9％,测定结果的相对标准偏差为2．6％-7．6％（n=6）。该方法具有测定有机磷农药种类多、快速等优点,能满足农药多残留分析的要求。     

Detecting bacteria and determining their susceptibility to antibiotics by stochastic confinement in nanoliter droplets using plug-based microfluidics

This article describes plug-based microfluidic technology that enables rapid detection and drug susceptibility screening of bacteria in samples, including complex biological matrices, without pre-incubation. Unlike conventional bacterial culture and detection methods, which rely on incubation of a sample to increase the concentration of bacteria to detectable levels, this method confines individual bacteria into droplets nanoliters in volume. When single cells are confined into plugs of small volume such that the loading is less than one bacterium per plug, the detection time is proportional to plug volume. Confinement increases cell density and allows released molecules to accumulate around the cell, eliminating the pre-incubation step and reducing the time required to detect the bacteria. We refer to this approach as 'stochastic confinement'. Using the microfluidic hybrid method, this technology was used to determine the antibiogram - or chart of antibiotic sensitivity - of methicillin-resistant Staphylococcus aureus (MRSA) to many antibiotics in a single experiment and to measure the minimal inhibitory concentration (MIC) of the drug cefoxitin (CFX) against this strain. In addition, this technology was used to distinguish between sensitive and resistant strains of S. aureus in samples of human blood plasma. High-throughput microfluidic techniques combined with single-cell measurements also enable multiple tests to be performed simultaneously on a single sample containing bacteria. This technology may provide a method of rapid and effective patient-specific treatment of bacterial infections and could be extended to a variety of applications that require multiple functional tests of bacterial samples on reduced timescales.     

微流控纸芯片在环境分析检测中的应用

近年来,微流控纸芯片由于低成本、便携化、检测快等优点,在需要快速检测的环境分析领域中展现出了巨大的应用前景.该综述从微流控纸芯片在环境分析中的应用角度,总结归纳了微流控纸芯片在环境分析中的最新研究进展,并展望了其在未来的发展趋势与挑战.论文内容引用150余篇源于科学引文索引(SCI)与中文核心期刊中的相关论文.该综述包...     

Recent progress on microfluidic biosensors for rapid detection of pathogenic bacteria

Rapid on-site detection of pathogenic bacteria with high sensitivity and specificity is becoming an urgent need in public health assurance, medical diagnostics, environmental monitoring, and food safety fields. Despite being reliable and widely used, the existing methods of bacteria detection are cumbersome and time-consuming, which is not conducive to field detection. Microfluidic lab-on-a-chip technology has provided a detective tool for various analytes, due to its miniaturization, portabilit...     

Rapid detection of organophosphorus pesticide residue on Prussian blue modified dual-channel screen-printed electrodes combing with portable potentiostat

A new method consisted of a dual-channel screen-printed electrode (DSPE) efficient modified with Prussian blue and acetylcholinesterase was developed for the rapid detection of organophosphorus pesticide residues.     

高分辨质谱技术在农药残留检测中的应用

农药残留检测是农产品中有害物质控制的重要组成部分,随着农药残留限量标准体系的发展完善,农药残留检测方法也在不断进步。近年来质谱技术发展迅速,已被广泛应用于农药残留检测领域,高分辨质谱由于具有较高的分辨率和质量精确度,在复杂基质的农药多残留高通量检测中发挥着越来越重要的作用。本文从高分辨质谱与液相色谱、气相色谱及其他分离模式联用等方面出发,简述了近5年来高分辨质谱在农药残留检测中的应用,对目前高分辨质谱在农药残留检测应用中发现的问题进行了讨论,并对其未来发展趋势进行展望。     

化学发光联用技术在兽药残留分析中的应用进展

本文对近年来化学发光联用技术在兽药残留分析中的应用进展进行了评述,主要包括化学发光免疫分析、分子印迹-化学发光分析、微流控芯片-化学发光检测等,引用文献31篇.     

微流控芯片技术在生殖研究中的进展

生殖是生物体最基本特征之一，是物种得以延续和进化的保证。近年来，微流控芯片系统得到了迅猛发展，技术也逐渐成熟，具有良好的应用前景。在生殖研究中，微流控技术具有以下优势：微管道的形状和尺寸可以灵活设计，从而更好地模拟生理环境；微流控芯片对样品的消耗量低；微流控技术具有很高的集成性。微流控技术已被应用到精子活力评价与筛选、精子的化学趋向性筛选、卵丘细胞去除、透明带移除、卵细胞定位与筛选、受精过程、早期胚胎培养以及生殖器官模拟等各个方面。该文着重介绍近几年基于微流控技术生殖研究的最新进展，并对其应用前景进行展望。