高效液相色谱柱后衍生测定鸡组织中甲基盐霉素残留量

建立了鸡组织中甲基盐霉素的高效液相色谱柱后衍生化分析方法.样品经异辛烷提取,离心后上层有机相过硅胶固相萃取小柱,洗脱液浓缩后用V(甲醇)∶ V(水)=90∶ 10混合液溶解.采用Inertsil ODS-3 C18柱,以V(甲醇): V(乙酸)∶ V(水)=94∶ 3∶ 3为流动相,香草醛为衍生剂进行高效液相色谱柱后衍生分析,520 nm检测,外标法定量.方法检出限为6 μg/kg; 定量限为20 μg/kg; 添加浓度在20～1800 μg/kg范围内,平均添加回收率为76.4%～93.1%; 批内相对标准偏差(RSD)在2.6%～8.9%之间; 批间相对标准偏差(RSD)在4.7%～9.7%之间.样品浓度在0.07～10.0 mg/L范围内与峰面积呈良好的线性关系,r>0.9993.     

高效液相色谱荧光检测法测定蔬菜中残留的甲氨基阿维菌素苯甲酸盐

建立了甘蓝和蘑菇中甲氨基阿维菌素苯甲酸盐的固相萃取-高效液相色谱荧光分析方法。蔬菜样品用乙酸乙酯提取,提取液旋转浓缩近干后用少量乙酸乙酯溶解,再经PRS固相萃取(SPE)柱净化,洗脱液经氮气吹干后用氮甲基咪唑和三氟乙酸酐衍生,衍生物用高效液相色谱分析,采用外标法定量。在添加浓度1.0～20.0 μg/kg范围内,平均添加回收率为78.6%～84.9%,日内相对标准偏差(RSD)为2.7%～6.0%,日间RSD为3.1%～8.9%,检出限为0.10 μg/kg。甲氨基阿维菌素苯甲酸盐衍生物在0.002～0.10 mg/L范围内呈良好的线性关系,相关系数为0.9999。     

气相色谱-串联质谱法分析茶叶中11种除草剂

优化了茶叶中11种除草剂的前处理方法和串联质谱检测条件。样品经乙腈提取,石墨化炭黑/丙基乙二胺(Graphitized Carbon Blacks/primarySecondary Amine,GCB/PSA)固相萃取小柱净化,采用大体积进样,串联四极杆质谱多反应监测(MRM)进行测定。11种除草剂在质量浓度为0.050～0.500mg/kg范围内与峰面积呈良好线性关系,检出限(10S/N)在1.3～13.0μg/kg之间;添加浓度为0.05 mg/kg时,11种农药的平均回收率为74.8%～98.8%,RSD为8.6%～15%;添加浓度为0.25 mg/kg时,11种农药的平均回收率为78.5%～95.4%,RSD为7.4%～15%(n=5)。方法适用于茶叶中上述11种除草剂的快速筛查。     

固相萃取-气相色谱/质谱法测定人参种植土壤中48种农药残留

采用固相萃取方法,结合气相色谱-质谱(GC/MS)建立了同时检测人参种植土壤中48种农药残留的分析方法。研究了萃取剂、固相萃取柱、洗脱剂种类和用量对样品提取及净化效果的影响,并考察了共萃取基质和基质效应,质谱采用选择离子监测(SIM)模式,外标法定量。结果表明,48种农药在各自的线性范围内,线性关系良好(r~20.995);在3个添加水平(10、20、100μg/kg)的回收率为86.3%～128.8%,相对标准偏差(RSD,n=6)为1.5%～14.6%。48种农药的检出限为2.0～6.0μg/kg,定量限为5.0～20.0μg/kg。该方法样品前处理简单、高效,测定的准确性好、灵敏度高,适用于人参种植土壤中多种类农药残留的筛选与测定。     

气相色谱-质谱法测定肝脏组织中盐酸克伦特罗和盐酸莱克多巴胺

建立了同时测定动物肝组织中盐酸克伦特罗和盐酸莱克多巴胺残留量的固相萃取-气相色谱-质谱分析方法。动物肝组织样品在碱化的条件下用乙酸乙酯和异丙醇混合溶剂提取,提取液浓缩后用乙酸乙酯溶解,然后再用稀盐酸反萃取去除脂肪,调pH值后经SCX固相萃取(SPE)柱净化,洗脱液经氮气吹干后经双三甲基硅基三氟乙酰氨(BSTFA)衍生,采用选择离子模式(盐酸克伦特罗:86、212、262、277,盐酸莱克多巴胺:163、192、234、250)进行测定,外标法定量。盐酸克伦特罗和盐酸莱克多巴胺的检出限分别为0.30和1.00μg/kg。盐酸克伦特罗添加浓度在1.0~5.0μg/kg范围内,添加回收率为77.4%~88.3%;相对标准偏差(RSD)为3.1%~5.1%;盐酸莱克多巴胺添加浓度在4.0~20.0μg/kg,添加回收率为69.8%~82.1%;相对标准偏差(RSD)为3.5%~4.9%;衍生物的峰面积与被测物浓度分别在0.003~1.00 mg/L和0.012~4.00 mg/L范围内呈良好的线性关系,线性回归系数均大于0.999。     

固相萃取-气质联用法测定啤酒中9种有机磷农药残留

建立啤酒中9种有机磷农药的固相萃取-气质联用分析方法.采用C18固相萃取小柱对啤酒中的有机磷农药进行提取、净化,用乙酸乙酯洗脱后供气相色谱-质谱分析,用基质匹配标准校正方法补偿基质效应.当添加浓度为50 μg/kg和100μg/kg时,平均回收率为80.3%～95.0%;测量结果的相对标准偏差为1.97%～8.28%(n=6);方法的检出限为1.20～15.3μg/kg.该方法可用于啤酒中痕量有机磷农药残留的测定.     

猪肉中四环素类抗生素残留的固相萃取-高效液相色谱荧光测定法

采用固相萃取技术富集、分离猪肉中四环素、土霉素、金霉素、强力霉素4种四环素类抗生素,采用反相高效液相色谱荧光法测定.对固相萃取柱、流动相、检测器等条件进行了优化选择,4种物质的检出限为0.03～ 0.05μg/mL在0.02～0.20 mg/kg添加水平,4种抗生素的加标回收率为60%～91%之间,相对标准偏差(RSD,n=5)为2.1%～5.1%.     

LC-MS/MS检测蜂胶中硝基呋喃类代谢物的残留

建立了蜂胶中硝基呋喃类代谢物液相色谱-串联质谱检测方法。样品经固相萃取、衍生、乙酸乙酯提取后进行质谱分析。在1.0、2.0、5.0μg/kg 3个添加水平下,硝基呋喃类代谢物的平均回收率为92.6%～99.3%,日内相对标准偏差小于10%,日间相对标准偏差小于15%。在0.5～20 ng/mL范围内呈良好的线性(r>0.99),检测限为0.25μg/kg,定量限为1.0μg/kg。方法适用于蜂胶中硝基呋喃类代谢物的分析确证。     

液相色谱串联质谱法测定动物性食品中4种抗球虫药

建立动物性食品中4种抗球虫药的液相色谱-串联质谱法。4,4’-二硝基均二苯脲、地克珠利、托曲珠利砜、托曲珠利经C₁₈色谱柱分离后,在低分辨质谱仪上以多反应监测模式检测,在高分辨质谱仪上以一级质谱全扫描/数据依赖的二级质谱全扫描模式检测,内标标准曲线法进行定量。4种抗球虫药的质量浓度在0.50～50 ng/mL范围内线性关系良好,相关系数均不低于0.999 2。分散固相萃取的加标回收率为87.5%～120.4%,测定结果的相对标准偏差不大于7.5%(n=6);固相萃取的加标回收率为86.7%～111.8%,测定结果的相对标准偏差不大于9.4%(n=6)。分散固相萃取-低分辨质谱法的检出限为0.11～2.1μg/kg,定量限为0.12～2.1μg/kg;分散固相萃取-高分辨质谱法的检出限为0.050～0.33μg/kg,定量限为0.17～1.1μg/kg;固相萃取-低分辨质谱法的检出限为0.11～0.52μg/kg,定量限为0.14～0.52μg/kg;固相萃取-高分辨质谱法的检出限为0.013～0.30μg/kg,定量限为0.043～1.0μg/kg。两种样品处理方...     

同位素稀释高效液相色谱串联质谱法测定猪肝中地塞米松和倍他米松残留量

建立了同位素稀释高效液相色谱串联质谱法测定猪肝中地塞米松和倍他米松残留量的分析方法。样品经酶解后用乙腈提取,再经C18固相萃取和碳酸钠溶液液液萃取净化,净化后的样品经氮气吹干后用流动相溶解。采用Hypercarb C18柱,以乙腈-水-甲酸(95∶5∶0.5,V/V)混合溶液为流动相,进行高效液相色谱串联质谱分析,同位素内标法定量分析。地塞米松和倍他米松的检出限为别为0.12和0.14μg/kg,定量限分别为0.42和0.47μg/kg。在添加浓度0.75～2.0μg/kg范围内,平均添加回收率为97.3%～111%,批内和批间相对标准偏差(RSD)分别为1.85%～5.65%和2.78%～7.98%。待测物定量离子对峰面积与内标物峰面积比值与标样浓度在10～500μg/L范围内呈良好的线性关系,线性回归系数大于0.9997。     

Determination and study on residue and dissipation of benazolin-ethyl and quizalofop-p-ethyl in rape and soil

A QuEChERS (quick, easy, cheap, effective, rugged, and safe) method for the determination of benazolin-ethyl and quizalofop-p-ethyl in rape and soil by high-performance liquid chromatography-tandem mass spectrometry has been developed in this study. The residue and dissipation of benazolin-ethyl and quizalofop-p-ethyl in rape and soil were determined with the developed method. The half-lives of benazolin-ethyl in rape straw and soil were 3.7–5.1 days and 14.3–26.3 days, respectively. The half-lives of quizalofop-p-ethyl in rape straw and soil were 5.0-6.1 days and 0.3–9.7 days, respectively. The residue of benazolin-ethyl and quizalofop-p-ethyl in rapeseed and soil were below the detection limit (i.e., 0.5?mg?kg^?1, the maximum residue level of European Union for quizalofop-p-ethyl).     

Methods for determination of hexachlorobenzene and pentachlorophenol in soil samples

The efficiency of methods for the determination of hexachlorobenzene (HCB) and pentachlorophenol (PCP) in soil samples was evaluated. An on-line method was applied for HCB determination. Soil samples were transferred to chromatographic columns prepacked with alumina. The HCB elution was processed with n-hexane. The PCP was extracted from soil samples with n-hexane-acetone in an ultrasonic bath. After re-extraction with K(2)CO(3) solution PCP was acetylated with acetic anhydride. The pentachlorophenyl acetate derivative was then extracted with n-hexane. The HCB and PCP derivative were analyzed by gas chromatography with electron capture detection (GC-ECD). Mean recoveries obtained from soil samples fortified at levels of 0.5; 4 and 20 ng g(-1), ranged from 91 to 100% for HCB, and for PCP, at levels of 10; 40 and 200 ng g(-1), ranged from 88 to 101%. These results demonstrated the efficiency of the proposed methods.     

气相色谱法测定苹果和土壤中的高效氯氟氰菊酯

建立了改进的QuEChERS-气相色谱检测苹果和土壤中高效氯氟氰菊酯残留的分析方法,考察和评价了苹果和土壤两种基质对高效氯氟氰菊酯的基质效应。苹果和土壤样品均用乙腈提取,经石墨化碳黑（GCB）净化后直接进样分析。结果表明：在优化后的QuEChERS条件下,高效氯氟氰菊酯在0.05~10 mg/L范围内线性关系良好,相关系数（R²）大于0.999,检出限为0.12~0.15 μg/kg,定量限为0.38~0.50 μg/kg。用基质标准曲线定量时,高效氯氟氰菊酯在土壤和苹果中的回收率分别为88.29%~97.65%和80.70%~98.69%。苹果和土壤样品对高效氯氟氰菊酯都表现出基质增强效应。该方法的回收率均能达到残留分析要求,用基质配制标准溶液能够有效、方便地校正气相色谱-电子捕获检测器测定高效氯氟氰菊酯残留时的基质效应,且能应用于苹果和土壤实际样品的检测。     

土壤中绿黄隆残留量分析方法的研究

本文确立了土壤中绿黄隆残留量的间接气相色谱分析方法，用０．１５ｍｏｌ／Ｌ ＮａＨＣＯ３提取土样，二氯甲烷洗涤初步纯化后，在水浴上加热水解，再用二氯甲烷萃取，弗罗里硅土柱净化，最后用气相色谱－电子捕获检测器检测水解产物邻氯苯磺酰胺。土壤中添加回收率７８．５％－９０．８％，检测极限０．３ｎｇ／ｇ。     

基于QuEChERS净化/气相色谱法测定蔬菜及水果中16种有机氯农药残留

该文建立了蔬菜及水果中16种有机氯农药残留的QuEChERS净化/气相色谱快速检测方法。样品经1%冰乙酸乙腈处理,QuEChERS净化,气相色谱分离后,以色谱峰保留时间定性,外标法定量。结果表明:16种有机氯农药在2.0~100μg/L质量浓度范围内的线性关系良好,相关系数均大于0.99,检出限为0.16~2.90μg/L,在4种基质(油菜、黄瓜、橙子、苹果)中的加标回收率为70.1%~119%,相对标准偏差(RSD)为0.23%~5.2%。与其它前处理方法相比,该方法简便、快速、准确、高效,可用于蔬菜及水果样品中有机氯残留的高通量快速筛查。     

Determination and study on degradation dynamics of fungicide validamycin a residue in soil using pre-column derivatization and capillary gas chromatography

A method for determining validamycin A residue in soil utilizing pre-column derivatization and gas chromatography was developed. Validamycin A was extracted from soil samples by 10% ammonia solution without additional clean-up step and then was derivatized with N,O-bis(trimethylsilyl)acetamide. Derivative of validamycin A was analyzed by gas chromatography on a capillary column. The method showed good linearity in the range of 4.4–142.0 mg/L (r ₂ = 0.9997). The average recoveries were 98.82 and 98.61% with relative standard deviations 1.95 and 2.87% at spiking levels 0.2 and 2.0 mg/kg, respectively. The limit of detection of validamycin A in soil was 0.2 mg/kg. The degradation dynamics of validamycin A in soil was studied. The result shows that validamycin A degradation in soil in the open field in Beijing suburb can be described by the equation c = 6.6109e ^−0.0196t ; the half-life is 35.4 h. The article is published in the original.     

Analysis of triallate residues in cereals and soil by gas chromatography with ion-trap detection.

Triallate residues in barley seedlings and soil samples were determined by gas chromatography with ion-trap detection. Soil was extracted with methanol on a mechanical shaker, and plants were extracted with acetonitrile in a Sorvall homogenizer. After evaporation of the organic solvents, the residue was dissolved in hexane, and plants extracts were cleaned-up on an alumina column. Gas chromatographic analysis was carried out using a BP-1 fused-silica capillary column with helium as carrier gas. To quantitate residues the total-ion chromatogram was obtained and then the selected-ion monitoring chromatograms were displayed at m/z 86 for triallate and at m/z 154 for the internal standard, methyl-(4-amino-2-chloro)-benzoate. The average recovery through the method from barley and soil samples was always higher than 80%. The limit of detection in the selected-ion mode was 0.01 mg/kg. Barley and soil samples treated with triallate were also analysed. A good agreement was observed between results obtained by this method and by gas chromatography with nitrogen-phosphorus detection.     

Determination of Aroclor 1260 in soil samples by gas chromatography with mass spectrometry and solid‐phase microextraction

A novel fast screening method was developed for the determination of polychlorinated biphenyls that are constituents of the commercial mixture, Aroclor 1260, in soil matrices by gas chromatography with mass spectrometry combined with solid‐phase microextraction. Nonequilibrium headspace solid‐phase microextraction with a 100 μm polydimethylsiloxane fiber was used to extract polychlorinated biphenyls from 0.5 g of soil matrix. The use of 2 mL of saturated potassium dichromate in 6 M sulfuric acid solution improved the reproducibility of the extractions and the mass transfer of the polychlorinated biphenyls from the soil matrix to the microextraction fiber via the headspace. The extraction time was 30 min at 100°C. The percent recoveries, which were evaluated using an Aroclor 1260 standard and liquid injection, were within the range of 54.9–65.7%. Two‐way extracted ion chromatogram data were used to construct calibration curves. The relative error was <±15% and the relative standard deviation was <15%, which are respective measures of the accuracy and precision. The method was validated with certified soil samples and the predicted concentrations for Aroclor 1260 agreed with the certified values. The method was demonstrated to be linear from 10 to 1000 ng/g for Aroclor 1260 in dry soil.     

气相色谱-质谱法同时测定土壤中的4种丙烯酸酯类农药

建立快速溶剂萃取-气相色谱质谱联用法同时测定土壤中的4种丙烯酸酯类(嘧菌酯,嘧菌胺,苯氧菌胺,醚菌酯)残留量的分析方法。将随机采集到的土壤样品自然风干,粉碎过筛。称取过筛后的样品5 g,置于萃取池中,以丙酮-乙酸乙酯(体积比为1∶1)作为萃取溶剂,于加速溶剂萃取仪中进行提取,收集提取液,氮吹至近干,用丙酮定容至1 mL,以0.45μm滤膜过滤后,上GC-MS/MS仪分析,色谱峰面积外标法定量检测。4种丙烯酸酯类的质量浓度在0.05~5.0μg/mL范围内与其色谱峰面积呈良好的线性关系,检出限为0.006~0.010 mg/kg,加标回收率为91.4%~94.6%,测定结果的相对标准偏差为2.48%~4.29%(n=6)。该方法前处理简单,定性及定量结果准确,适用于土壤中丙烯酸酯类残留的监测。     

超声波提取-气相色谱法测定土壤中21种酚类化合物

建立了超声波提取-气相色谱法同时测定土壤中21种酚类化合物的分析方法。用二氯甲烷和正己烷混合溶剂提取土壤中的酚类化合物,提取液经碱性水溶液分配净化,去除非酸性有机杂质,再酸化萃取酚类化合物,浓缩后采用气相色谱-氢火焰离子化检测器进行检测,外标法定量。以10 g土壤样品计,酚类化合物的检出限为0.01~0.06 mg/kg。实际样品添加回收试验的回收率为62.9%~111.4%,相对标准偏差为4.3%~24.0%(n=6),准确度和精密度均较好。结果表明:该法操作方便,净化效果好,可用于土壤中多种酚类化合物的测定。