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A demanding task in pesticide residue analysis is yet the development of multi-residue methods for the determination of pesticides in vegetables with relatively high fat content (i.e. edible oils and fatty vegetables). The separation of pesticides and other chemical contaminants from high-fat food samples prior to subsequent steps in the analytical process is yet a challenging issue to which much effort in method development has being applied. This review addresses the main sample treatment methodologies for pesticide residue analysis in fatty vegetable matrices. Even with the advent of advanced hyphenated techniques based on mass spectrometry these complex fatty matrices usually require extensive sample extraction and purification. Current methods involve the use of one or the combination of some of the following techniques for both the sample extraction and clean-up steps: liquid-liquid partitioning, solid-phase extraction (SPE), gel-permeation chromatography (GPC), matrix solid-phase dispersion (MSPD), etc. An overview of methods developed for these contaminants in fatty vegetables matrices is presented. Sample extraction and purification techniques are discussed and their most recent applications are highlighted. This review emphasizes that sample preparation is a critical step, but also the determination method is, and cannot be treated separately from sample treatment. In recent years, the appearance and use of new, more polar pesticides has fostered the development of liquid chromatography/mass spectrometry (LC-MS) besides gas chromatography. The main features of LC-MS for the analysis of multi-class pesticides in fatty vegetable samples will be also underlined, with an emphasis on the multi-class, multi-residue strategy and the difficulties associated.  相似文献
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Summary Static headspace sampling combined with gas chromatography using open-tubular (capillary) columns for the characterization of the flavour of raw vegetables and some vegetable products is described. In order to avoid alteration of the composition of the volatiles, the sample was thermostated for a short time only. Although equilibrium between vapour and sample was not established the reproducibility of such conditions is demonstrated. Typical chromatograms are given; the most characteristic compounds present were identified by mass spectrometry. Enlarged text of a poster presented at the Twelfth International symposium on Capillary Chromatography, September 11–14, 1990, Kobe, Japan  相似文献
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通过气相色谱-负化学离子源质谱技术建立了同时检测18种农药残留的分析方法. 样品经正己烷和丙酮混合溶剂及正己烷提取后, 用活性炭-中性氧化铝混合小柱净化, 再由气相色谱-负化学离子源质谱分时段选择离子监测技术进行测定. 一次进样就能得到18种农药残留结果;各农药在0.005、 0.01和0.02 mg/kg 3个添加水平的平均回收率在70.2%~115.3%之间, RSD<12%, 检出限为0.01~6 μg/kg, 方法可应用于8种植物性产品中的农残检测.  相似文献
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建立了高效液相色谱-串联质谱法(HPLC-MS/MS)测定植物源食品中环磺酮残留量的分析方法.样品经改进的QuEChERS方法一步完成萃取净化,经酸化乙腈(含0.1%(V/V)甲酸的乙腈)提取,经石墨化碳黑(GCB)净化,提取液经离心后直接过膜上机检测.HPLC-MS/MS方法以0.1%(V/V)甲酸-乙腈为流动相,在0.25 mL/min流速下梯度洗脱,采用C18色谱柱进行液相色谱分离,电喷雾正离子电离(ESI+),多重反应监测模式(MRM)检测,基质匹配外标法进行定量分析.结果表明,在10种基质(玉米、大米、小麦、葡萄、苹果、葡萄干、枸杞、西红柿、黄瓜、白菜)中,环磺酮在0.5 ~ 100.0 ng/mL范围内线性关系良好,相关系数均大干0.996;方法定量限(S/N≥10)为1.0 μg/kg;在1.0,2.0和10.0μg/kg添加水平下,环磺酮的平均回收率为82.0% ~111.8%,相对标准偏差为3.0%~14.9%.本方法高效快捷,灵敏度、准确度和精密度均符合农药残留检测要求.  相似文献
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建立了QuEChERS前处理-高效液相色谱-串联质谱法(HPLC-MS/MS)同时检测植物源性食品中噻氟隆和炔草隆残留的分析方法.样品以酸化乙腈提取,经石墨化碳黑(GCB)净化.采用C18色谱柱进行分离,以甲醇-0.1%甲酸溶液(含5 mmol/mL乙酸铵)为流动相,梯度洗脱.质谱采用电啧雾正离子电离(ESI+),多重反应监测模式(MRM)检测.以保留时间和特征离子对进行定性,基质匹配外标法定量.结果表明:在葡萄、葡萄干、西红柿、大米、苹果、枸杞、黄瓜、小麦粉、白菜9种基质中,噻氟隆和炔草隆在各自线性范围内线性关系良好(相关系数r2均大于0.997);噻氟隆和炔草隆的定量限(S/N=10)分别为0.4、1.0 μg/kg,在3个加标水平(1、2、10倍定量限)下,噻氟隆的回收率为84.7%~107.7%,相对标准偏差为4.2%~16.3%;炔草隆的回收率为74.7%~110.0%,相对标准偏差为4.3%~12.8%.该方法简单、快速、准确、灵敏、安全,适用于植物源性食品中噻氟隆和炔草隆残留的快速确证和定量分析.  相似文献
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建立了植物性食品(苹果、芹菜、甜椒、干扁豆)中链霉素(Streptomycin,STR)和双氢链霉素(Dihydrostreptomycin,DHS)的高效液相色谱-串联质谱(HPLC-MS/MS)检测方法。样品经磷酸盐缓冲溶液提取,借助WCX固相萃取柱富集净化后,采用Atlantis Hilic Silica亲水作用色谱柱(100 mm×30 mm,3 μm)分离,乙腈-01 mol/L甲酸铵和01%甲酸溶液等度洗脱,以电喷雾电离串联质谱多反应监测(MRM)正离子模式进行检测,外标法定量。结果显示,链霉素和双氢链霉素在10~120 μg/L质量浓度范围内线性良好,相关系数(r)均大于0999,定量下限均为125 μg/kg。本底空白的4种样品基质在3个添加水平(125、250、500 μg/kg)下的平均回收率为836%~101%,相对标准偏差为23%~78%。该方法无需使用对LC-MS联用仪造成污染的离子对试剂,且方法操作简便、快速、可靠、稳定,能满足大部分植物性食品中链霉素和双氢链霉素的检测需要。  相似文献
7.
曲栗  李优  曾静  盛永刚  伊雄海  程甲 《色谱》2017,35(7):778-784
建立了气相色谱-三重四极杆质谱(GC-MS/MS)同时测定植物源性食品中20种拟除虫菊酯类农药残留量的方法。样品经丙酮-正己烷(1:1,v/v)提取,活性炭小柱净化,外标法定量。目标物在0.005~1.0 mg/L范围内呈良好的线性相关,相关系数(r2)均不小于0.990,方法的检出限(信噪比(S/N) > 3)均为2.0 μ g/kg,定量限(S/N > 10)均为5.0 μ g/kg。分别在11种基质中做低、中、高3个添加水平的加标回收试验,该方法的平均回收率为75.2%~107%,相对标准偏差(RSD,n=6)为3.08%~12.1%。该方法前处理步骤简便,特异性强,适用范围广,适用于植物源性食品中20种拟除虫菊酯类农药的筛查和确证。  相似文献
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