分散液液微萃取技术及其在食品和环境农药残留检测中的应用

分散液液微萃取是一种新型的样品前处理技术,该技术集萃取和浓缩于一体,具有操作简单、快速、成本低、富集效率高且对环境友好等优点。本文就分散液液微萃取原理、操作过程、影响因素进行介绍,重点综述该项新技术在食品和环境农药残留检测中的应用,并对其应用前景进行展望。     

食品中苯甲酸和山梨酸检测样品前处理方法研究进展

近年来,国内的食品安全问题越来越受到重视,有关食品中苯甲酸和山梨酸等防腐剂检测的报道层出不穷。苯甲酸和山梨酸的检测方法一般为气相色谱法和液相色谱法,而样品前处理方法则普遍较复杂,且直接影响着处理过程中防腐剂的提取率,在很大程度上影响着检测结果,同时也决定了整个检测过程的复杂程度、时间及成本。传统前处理方法一般包括稀释进样、超声提取,虽然操作简单,但适用范围狭窄,不能起到彻底除杂的效果;而固相微萃取、液相微萃取、分散萃取等方法则属于较新颖的方法,能够在净化样品的基础上,提取出目标防腐剂,为样品前处理的方法提供了新思路。并对2014年之前检测食品中苯甲酸和山梨酸的文献中提到的样品前处理方法进行了汇总和分析。     

液相微萃取技术在食品分析中的应用

液相微萃取(LPME)是一种微型的环境友好型的样品前处理技术,集萃取、富集、浓缩于一体,对整个化学领域具有重要意义,尤其在食品分析领域,它已成为样品前处理技术的研究热点。液相微萃取克服了传统方法的弊端,具有有机试剂用量少,操作简单、快速,富集因子高等优点。基于液相微萃取的前处理技术也在不断开发应用,通过总结液相微萃取的原理及其在食品分析领域的应用,讨论不同前处理技术的优缺点,并对其未来发展趋势进行展望。     

液相微萃取技术及其在食品分析中应用现状

液相微萃取是一种绿色环保的样品前处理技术,具有选择性好、操作简单、快速、富集倍数高、所需有机溶剂用量少等特点而成为一种备受关注的新型样品分离富集技术。近些年,该技术已经在水样、土壤、饮品及食品等样品的分析中得到广泛应用。本文综述了液相微萃取技术近期的研究进展及其在食品安全分析领域的应用,包括饮品、蔬菜水果、谷物及动物性组织等食品中农药、兽药、酚类物质、持久性污染物及其他一些物质的分析检测,并对其发展趋势进行展望。     

微型分光光度计与液相微萃取技术耦合研究进展

液相微萃取是一种微型化样品前处理技术,在萃取过程中只需要极少量的萃取剂,既可节约成本,也减少了萃取剂对环境和分析人员健康的危害。微型分光光度计操作简单,便于携带,可用于现场快速分析。因此微型分光光度计和液相微萃取技术的耦合受到越来越多的关注。文章详细综述了这种耦合技术的研究进展,并且展望了未来的研究方向。     

分散液液微萃取技术及其在食品和环境农药残留检测中的运用

分散液液微萃取技术(DLLME)是一种新型技术,可以实现对检测样品的前处理,能够有效降低检测成本,提高检测效率,更加方便快捷地实现对食品和环境中的农药残留检测。一、分散液液微萃取技术概述DLLME在应用过程中由于受到分散剂的影响,样品萃取剂会形成更为分散细密的液滴。随着检测时间的增加,萃取液形成的小液滴会逐渐分散,并逐渐呈现出乳浊液,乳浊液主要分层为水——分散剂——萃取剂。     

固相微萃取技术在食品安全检验中的应用研究

固相微萃取技术（SPME技术）是一种新型的样品前处理技术，也是一种新的分析技术。该技术与传统的样品前处理技术相比，具有简单、快速、高效等特点，目前已广泛应用于食品安全领域。近年来，随着我国科学技术的不断发展，食品安全检验领域中固相微萃取技术也有了较大的发展。本文首先介绍了固相微萃取技术的原理，然后对该技术在食品安全检验中的应用进行了研究，希望可以为今后该领域的研究提供一些参考。     

液相微萃取-气相色谱质谱法测定纺织品中24种禁用偶氮染料

应用分散液相微萃取技术,对纺织品检测国家标准(GB/T 1752-2011)中样品前处理方法进行了改进,建立了纺织品中源于偶氮染料的芳香胺的提取新方法.确立了添加1.0 mL丙酮为分散剂、200 μL三氯甲烷为萃取剂、萃取时间3 min、加入3％ NaS2O3作为萃取盐的最佳分散液相微萃取条件.对标准溶液和比对样品的测定结果表明:该方法线性范围广,相关系数r为0.9972～0.9998,检出限为0.1 μ g·mL-1,回收率达85％～93％,相对标准偏差小于4.3％.与国标法比较,该方法相对简单,检测快速,准确.     

食品和环境介质中双酚A前处理技术研究进展

双酚A是一种内分泌干扰物,在环境介质和食品包装材料中普遍存在,对生态环境和人体健康产生严重威胁,近年来受到人们的广泛关注。但实际样品中双酚A的浓度通常较低,且存在基质干扰,因此,直接检测比较困难,需要结合适当的前处理过程,以提高仪器的检出能力,保证分析结果的准确性和可靠性。就食品及环境介质中双酚A常用前处理技术,包括液-液微萃取、分散液-液微萃取、微波辅助萃取、加速溶剂萃取、固相萃取、固相微萃取、基质固相分散萃取、磁性固相萃取、分子印迹固相萃取和QuEChERS等技术,进行详细介绍、评价、总结和展望,为双酚A快速准确分析提供重要参考。     

食品安全分析中常用的样品前处理技术

食品基质复杂且有害物浓度较低,因而在食品安全分析检验中,样品前处理技术是关键。为提高食品安全检测中的分析效率和准确度,各种样品前处理技术不断地出现,极大地提高了食品分析的效率。本文总结近年来食品分析检测中常用的样品前处理技术,其中有液液萃取法、固相萃取法等传统前处理技术及固相微萃取法、磁性固相萃取技术、QuEChERS等新技术。     

食品中邻苯二甲酸酯分析与风险评估技术研究进展

食品安全已经成为了倍受社会关注的热点问题,成为了全社会共同面对的挑战。其中,作为目前最常见的增塑剂,邻苯二甲酸酯(phthalate esters,PAEs)在现代食品工业中应用广泛,其通过迁移、富集、转化对食品造成污染,现已引起了公众的高度关注。近年来,不同基质中PAEs的样品前处理技术(固相萃取、分散液液微萃取、Qu ECh ERS等)和分析技术(光谱法、色谱法、质谱联用法等)、毒性及风险评估成为了研究热点。本文对国内外PAEs最新的研究进展进行总结评述,对食品中PAEs的筛查技术进行探讨,为将来开展食品中PAEs的检测、评估提供建议和思考。其中,简便快捷的前处理技术结合高通量、高灵敏度的筛查技术将成为今后一段时间的研究热点。     

分散液液微萃取技术在乳制品分析中的应用

乳制品是人体重要的营养来源,其品质和安全关乎公众健康。由于乳制品基质效应明显,使相关指标的检测分析更具挑战性,亟需发展简便、高效、绿色的前处理方法改善基质干扰。分散液液微萃取技术(dispersive liquid-liquid microextraction,DLLME)是一种新型样品前处理方法,具有操作简单、溶剂消耗低和萃取效率高的特点,已广泛用于复杂基质样品中痕量无机/有机分析物的前处理。本文阐述了不同类型DLLME的原理特点,就DLLME技术在乳制品检测分析中的应用研究展开文献调研,展望了该技术在乳制品提取中的优化方向和应用前景,为乳制品分析提供新的技术选择。     

食品中赭曲霉毒素样品前处理及其检测方法研究进展

赭曲霉毒素广泛存在于谷物、葡萄和咖啡等众多食品中,具有极强的肝肾毒性和致畸、致癌作用,可经食物链传播效应累积在人体血液及内脏中,对人类健康造成巨大威胁。因此有必要建立食品中快速、灵敏的赭曲霉毒素分析方法,保障食品安全、维护人类的健康。食品基质复杂多样,且赭曲霉毒素在样品中含量极低,检测前需要高效的前处理技术对目标物进行分离和富集。该文综述了基于分子印迹材料、纳米石墨烯、生物材料、磁性纳米材料等新型分离介质的液相萃取、QuECHERS、固相萃取、免疫亲和层析和场辅助提取(微波辅助提取、磁性固相萃取、超声辅助提取)等前处理技术及色谱法、免疫分析法和生物传感器在食品中赭曲霉毒素分析中的应用,并对其发展趋势进行了展望。     

Application of Air-Assisted Liquid-Liquid Microextraction for Determination of Some Fluoroquinolones in Milk Powder and Egg Samples: Comparison with Conventional Dispersive Liquid-Liquid Microextraction

Herein, an air-assisted liquid-liquid microextraction (AALLME) has been described and compared to conventional dispersive liquid-liquid microextraction (DLLME) for the extraction/preconcentration of six fluoroquinolone compounds in milk powder and egg samples prior to high-performance liquid chromatography-UV detection (HPLC-UV). In order to compare the novel AALLME technique to the conventional DLLME technique, several parameters that influence the extraction efficiency were studied and optimized. Both methods have been validated for milk powder and egg analysis, obtaining limits of quantification lower than those usually permitted by legislation in food matrices, with precisions expressed as coefficients of variation lower than 8 % and recoveries between 72 and 115 % which were acceptable recoveries and repeatability. An AALLME method needs less organic solvent and shorter centrifugation time; therefore, it is more environmentally friendly and efficiently compared to DLLME.     

Development of a Dispersive Liquid–Liquid Microextraction Method for the Determination of α-Tocopherol in Pigmented Wheat by High-Performance Liquid Chromatography

A dispersive liquid–liquid microextraction (DLLME) method coupled to high-performance liquid chromatography was developed for the analysis of α-tocopherol in grain samples. The DLLME parameters including the type and volume of extractants, the volume of disperser and the addition of salt were examined. The optimized DLLME procedure consisted in the formation of a cloudy solution promoted by the fast addition to the sample (5 mL of saponified sample solution diluted with 5 mL of water) of a mixture of carbon tetrachloride (extraction solvent, 80 μL) and ethanol (dispersive solvent, 200 μL) without the addition of salt, followed by shaking for 5 min and centrifuging for 3 min at 5,000 rpm. Intra- and inter-day repeatability expressed as % RSD were 3.5 and 7.6 %, respectively. The limit of detection and the limit of quantification were 1.9 and 6.3 μg?L^?1. The comparison of this method with the national standardized extraction method, supercritical carbon dioxide extraction, accelerated solvent extraction, and conventional heat-reflux extraction indicates that the DLLME was accurate (no significant differences at the 0.05 % probability level), high efficient, low organic solvent-consuming, and low cost. This procedure was successfully applied to 42 samples of 14 types of purple wheat, for which the content of α-tocopherol exhibited a significantly negative correlation with the pigment content measured by a spectrophotometer. The recovery rates ranged from 90.5 to 103.7 %.     

Evaluation of Dispersive Liquid–Liquid Microextraction–HPLC–UV for Determination of Deoxynivalenol (DON) in Wheat Flour

A fast and simple method for the extraction of deoxynivalenol (DON) from wheat flour using dispersive liquid–liquid microextraction (DLLME) followed by high-performance liquid chromatography–UV detection has been developed and compared with immunoaffinity column cleanup (IAC) process. The influence of several important parameters on the extraction efficacy was studied. Under optimized conditions, a linear calibration curve was obtained in the range of 50–1,000 μg/L. Average recoveries of DON from spiked wheat samples at levels of 500 μg/kg for DLLME and IAC ranged from 72.9?±?1.6 and 85.5?±?3.1, respectively. A good correlation was found for spiked samples between DLLME and IAC methods. The limit of detection was 125 and 50 μg/kg for DLLME and IAC method, respectively. Advantages of DLLME method with respect to the IAC have been pointed out.     

金属有机框架材料在食品检测中应用的研究进展

食品安全问题始终是社会关注的热点之一。为保障食品安全和人类健康,对食品污染物进行检测是控制和消除其所造成风险的关键。因此,开发灵敏、准确的食品污染物检测方法具有十分重要的意义。金属有机框架（metal-organic frameworks,MOFs）是一类由金属离子或金属团簇与有机配体自组装而成的新型多孔晶体材料,具有孔隙率高、比表面积大、结构可调、功能多样等优点,越来越受到学界关注。MOFs可与多种检测技术、样品前处理技术相结合,在食品检测方面具有广泛的应用前景。本文综述了近些年MOFs及其复合物材料在食品检测中应用的研究进展,主要包括作为传感检测材料和作为色谱法样品前处理材料应用的研究,同时对其在食品安全领域中存在的应用问题进行了总结,并展望了其在食品安全领域未来的研究方向。     

Determination of Pesticides Residues in Brazilian Grape Juices Using GC-MS-SIM

The production of grape juice in Brazil is growing at a 30 % rate a year. To increase exports, a full complainment to food safety protocols, as those in the Codex Alimentarius, is mandatory. Simple and fast analytical methods are needed for quality assurance. The objective of this work was to develop and validate an analytical method for detection of pesticides residues (organochlorides, organophosphorides, and fungicides) in Brazilian whole grape juices. The analyses were performed by gas chromatography coupled to mass spectrometry, operating in selective ion monitoring. After liquid–liquid extraction, samples were preconcentrate using solid-phase extraction in Florisil. The limit of quantification ranged from 3.75 to 9.47 mg l^-1, and recovery varied from 84.0 % to 99.7 %, with RSD lower than 4.9 %. From a total of 99 Brazilian grape juices analyzed, pesticide residues were found in 32.     

Simultaneous determination of dehydroacetic acid,benzoic acid,sorbic acid,methylparaben and ethylparaben in foods by high-performance liquid chromatography

In this study, an analytical method was established and validated to determine the preservatives such as dehydroacetic acid, benzoic acid, sorbic acid, methylparaben and ethylparaben. The level of preservatives was measured by solvent extraction method adding purification process with carrez reagent and by high-performance liquid chromatography (HPLC). The developed analytical method was successfully applied to determine the concentration of preservatives in various food samples including jam, cheese and soy sauce, displaying high accuracy (recoveries between 87.8% and 110%) and precision (%RSD less than 5.92% and 7.72% for intra-day and inter-day, respectively). To verify the applicability of the improved test method, selected 13 food items and collected 521 samples were monitored. As a result, all the cases met the Korea standard guidelines. Consequently, this study is expected to contribute to the safety management of preservatives for domestic distribution and imported food.