GC测定山西产连翘中有机氯及拟除虫菊酯类农药残留

目的建立连翘中有机氯和拟除虫菊酯类农药残留的GC测定方法。方法样品用石油醚（60～90℃）-丙酮（4∶1）混合溶液超声提取,Florisil-氧化铝固相柱净化,用GC-ECD同时测定了9种有机氯和3种拟除虫菊酯类农药残留量。结果所测定12种农药标准曲线的相关系数r在0.999 2～0.999 9之间,回收率在80.69%～115.6%之间;17个样品（其中11个野生样品,6个栽培样品）中未检测到农药残留,3个栽培样品检测到γ-BCH和氯氰菊酯残留。结论该方法简便、快速、准确,可用于连翘中有机氯及拟除虫菊酯类农药的残留量测定;山西野生连翘生长环境优良,未受有机氯和拟除虫菊酯类农药污染。     

GC法测定中药材中有机氯及拟除虫菊酯类农药的残留

目的 建立中药材中有机氯和拟除虫菊酯类农药残留的测定方法.方法 样品用超声波提取、Florisil-活性炭同相柱净化,用ECD检测器同时测定了12种有机氯和拟除虫菊酯类农药.结果 所测定农药标准曲线的r为0.9959-0.9995,回收率为85.8%～109.8%.结论 新建方法简便、快速、准确,可用于中药材中12种农药的含量测定.     

毛细管气相色谱法同时测定果蔬食品中有机氯和拟除虫菊酯类农药残留量

目的建立毛细管气相色谱法测定果蔬食品中有机氯和拟除虫菊酯类农药残留量的快速检测方法。方法样品经搅拌成匀浆后,利用乙腈直接萃取,弗罗里矽柱净化,滤液浓缩干燥后正己烷定容,再通过Rtx-1毛细管柱,ECD气相色谱定性和定量。结果9种有机氯和拟除虫菊酯类农药在28min内能有效分离,定量分析呈良好的线性关系,相关系数均大于99%,在豆角、大白菜中的2个添加浓度水平回收率为80.2%～104.6%,RSD为3.1%～7.8%;在Rtx-1毛细管柱上最小检测浓度为0.002～0.007mg/kg,符合卫生标准要求。结论该方法样品处理简单,准确度和精密度好,成本低,适合果蔬食品中多种有机氯和拟除虫菊酯类农药残留的同时快速检测。     

毛细管气相色谱测定人参中有机氯与拟除虫菊酯20种农药的残留

目的:建立有机氯与拟除虫菊酯20种农药残留的气相色谱分析方法。方法:以石油醚-丙酮(1:1,v/v)为提取剂,提取液用弗罗里硅土柱层忻净化,5%乙醚的石油醚洗脱,采用 Rtx—1毛细管色谱柱(30 m×0.25 mm×0.25μm)分离样品,~(63)Ni—ECD 检测器进行检测。结果:在0.02 mg·kg~(-1)水平添加时的回收率(n=3)为72.9%～118.6%,相对标准偏差为2.8%～7.6%。方法检出限为有机氯农药0.001 mg·kg~(-1),拟除虫菊酯农药0.005 mg·kg~(-1)。结论:该方法可用于不同人参产品中的有机氯和拟除虫菊酯农药残留测定。     

采用相对效能因子法对枸杞中拟除虫菊酯类农药的慢性累积暴露评估

目的：对枸杞中拟除虫菊酯类农药残留带来的累积暴露量进行评估,并探讨相对效能因子法 (RPF)在中药中农药残留累积风险评估中的应用。方法：采用GC-MS/MS法对40批枸杞药材中15种拟除虫菊酯类农药进行检测分析。以溴氰菊酯作为指示农药,采用RPF法,计算拟除虫菊酯类农药的累积暴露量,并与每日允许摄入量(ADI)进行比较,分析风险。同时采用危害指数法(HI)评价累积风险,并对两种方法进行比较。结果：40批枸杞样品中共有4种拟除虫菊酯类农药检出,样品检出率为 84.5%,其中有67.6%的样品中检出2种及以上拟除虫菊酯类农药。通过RPF法和HI法计算得累积风险值分别为0.000205和0.000218,均远低于1,表明累积摄入风险较低。同时发现通过2种方法得出的风险评价一致,但不同方法中各农药的风险贡献值有较大差异,这与2种方法所选择的毒性判断终点不同有关。 结论：通过摄入枸杞中拟除虫菊酯类农药对人体产生的健康风险尚处于可接受水平,并且首次探索了 RPF法在中药农药残留累积评估中的应用,为逐步完善中药中农药残留风险评估系统提供了借鉴。     

吴茱萸中拟除虫菊酯类农药残留分析

目的:分析中药吴茱萸中拟除虫菊酯类农药残留,为其质量控制和标准制定提供科学依据。方法:应用 GC-MS 法研究拟除虫菊酯类农药在中药吴茱萸中的残留。吴茱萸样品经石油醚-丙酮(4:1,v/v)混合液超声提取,无水硫酸钠-氟罗里硅土-无水硫酸钠三层填料固相萃取小柱净化,以 GC 法对净化液进行检测。结果:一次进样可对吴茱萸样品中的5种拟除虫菊酯类农药准确定量和确证。在检测的11批生药吴茱萸中,皆有氯氰菊酯残留,其次为甲氰菊酯和氰戊菊酯,氯氟氰菊酯、溴氰菊酯未检出。结论:GC-MS 法是一种简单、快速、高灵敏度的检测中药吴茱萸中拟除虫菊酯类农药的方法,可达到同时定量和确证的目的,建议推广应用。     

蔬菜中有机氯和拟除虫菊酯农药残留量的测定

目的建立了蔬菜中8种有机氯农药和4种拟除虫菊酯农药残留气相色谱分析方法。方法样品用丙酮浸泡过夜,再用石油醚进行液液分配,提取液用弗罗里硅土柱净化,采用SE-54弹性石英毛细管柱分离,用GC-ECD同时检测。结果高、中、低3个水平添加时的回收率为87.5%~104.7%,相对标准偏差为2.2%~5.8%。该方法的检出限为:有机氯农药质量分数为5.0×10-8%~7.0×10-7%,拟除虫菊酯质量分数为5.0×10-7%~8.0×10-7%。结论可用于蔬菜中农药残留量测定。     

气相色谱双塔双柱法同时测定中药材中56种有机氯类及拟除虫菊酯类农药残留量

研究中药材中有机氯类及拟除虫菊酯类农药残留量的测定方法。样品经高速均质器均质提取, 依次经凝胶渗透色谱 (GPC) 和固相萃取柱 (SPE) 净化后, 用气相色谱双塔双柱进样, 双电子捕获检测器同时定性、定量测定。在3种中药材样品基质、3水平添加条件下, 56种农药的回收率大多在70.0%～110.0%, 相对标准偏差小于15%, 检测限大多低于0.01 mg·kg⁻¹, 符合农药多残留检测的要求。本法净化效果好、基质干扰小、灵敏度高、重现性好, 可用于中药材样品中有机氯类及拟除虫菊酯类农药残留量的检测。     

固相萃取-高效液相色谱法测定桔梗中拟除虫菊酯的农药残留

目的:建立桔梗中甲氰菊酯、高效氯氟氰菊酯、溴氰菊酯、氰戊菊酯、氯菊酯、联苯菊酯共6个拟除虫菊酯类农药残留的提取、净化及其残留量测定的方法。方法:样品运用石油醚提取,商品CARB/NH2小柱净化,乙腈-二氯甲烷(5∶95)洗脱,HPLC-DAD检测。色谱条件:采用Hypersil BDS C18(250 mm×4.6 mm,5μm)色谱柱,流动相为乙腈-水(70∶30),流速1 mL.min-1,检测波长230 nm。结果:样品4水平添加时的6个拟除虫菊酯类化合物回收率在75.63%～107.5%范围内,RSD在2.3%～9.9%范围内,可以满足农药残留分析的要求。结论:该方法灵敏度高,选择性强,操作简单、快速,净化效果好。可应用于桔梗药材中痕量农药残留的检测。     

GC-MS法检测中草药保健食品中的农药多残留

目的建立一种检测保健食品中的农药多残留的分析方法。方法样品用乙腈提取并经硅胶柱净化后供GC-MS分析。采用选择离子扫描方式,内标标准曲线法定量。结果 20种农药在47 min内达到理想的分离效果。以3个添加水平测定样品的回收率和相对标准偏差,回收率在72.95%和118.48%之间,RSD均小于13%。各农药检测限为0.001 0～0.004 4 mg·kg-1。结论该方法简便、快速、准确、灵敏,且重现性好,可用于中草药保健食品中多种农药残留的同时测定。     

川贝母与其它贝母的薄层色谱鉴别

目的用薄层色谱法区别川贝母与其它贝母.方法收集各种贝母的对口药材,分离得其总皂苷;再取部分酸水解得皂苷元;分别用薄层色谱法比较各种贝母的皂苷部分和皂苷元部份.结果得到中国现行药典载的四种植物来源的川贝母均含有、而其它贝母均未含有的薄层色谱斑点;结论这些斑点具有将川贝母区别于其它贝母的鉴别价值.     

超临界CO2提取的百合挥发油化学成分的GC-MS分析

目的 研究百合挥发油化学成分。方法 采用超临界CO₂提取方法,GC-MS联用技术鉴定百合挥发油成分,并用峰面积归一化法测定各成分的相对百分含量。结果 超临界CO₂流体萃取法提取的挥发油共鉴定出50种成分,占挥发油总成分的72.96%。结论 超临界提取百合挥发油成分多、效率高,与水蒸气蒸馏提取出的挥发油成分有差异。     

固相萃取-气相色谱串联质谱法测定温莪术中19种有机氯和有机磷农药残留

目的:建立固相萃取-气相色谱串联质谱法测定温莪术中11种有机磷和8种有机氯农药残留,对10种不同批次的温莪术样品进行农药残留测定。方法:温莪术样品用有机溶剂萃取法进行提取,提取溶剂选为乙腈,C18固相萃取小柱净化提取液,用气相色谱-质谱仪分析,采用选择离子模式测定,外标法定量。结果:19种农药成分的峰面积与其质量浓度均有良好的线性关系,相关系数在0.991～1.000。19种农药成分的加标回收率为60.5%～109.3%,RSD为3.9%～10.5%。结论:该方法简便、快速,灵敏度高,重复性好,能够准确地检测温莪术中19种农药残留。     

程序升温毛细管气质联用法同时快速测定30种农药和2种老鼠药(氟乙酰胺、毒鼠强)

目的 建立一种程序升温毛细管气质联用法同时快速测定30种农药和2种老鼠药（氟乙酰胺、毒鼠强）的测定方法。方法 样品用二氟甲烷萃取,无水硫酸钠脱水,气质联用法检测。结果 方法简便、高效、快速、准确、灵敏度高。加标回收率〉87．4％。结论 本法测定30种农药和2种老鼠药（氟乙酰胺、毒鼠强）,其检测结果均能符合食品卫生标准所规定的相关要求。     

Development of gas chromatography-mass spectrometry with microwave distillation and simultaneous solid-phase microextraction for rapid determination of volatile constituents in ginger

In this study, gas chromatography-mass spectrometry (GC-MS) following microwave distillation and solid-phase microextraction (MD-SPME) was developed for the analysis of essential oil compounds in fresh ginger. In the proposed method, the isolation, extraction and concentration of volatile components in ginger were carried out in one single step, using the MD-SPME technique, and the analytes on the SPME fiber were analyzed by GC-MS. Some parameters, including SPME fiber coating, microwave power and irradiation time, were optimized. The optimal experiment parameters obtained were: 65 microm PDMS/DVB SPME fiber, a microwave power of 400 W and an irradiation time of 2 min. To demonstrate its feasibility, MD-SPME was compared with conventional SPME for the extraction of essential oil compounds in fresh ginger. Using MD-SPME followed by GC-MS, 54 compounds were separated and identified in ginger, which mainly included geranial (5.25%), zingiberene (15.48%), beta-sesquiphellandrene (5.54%) and beta-phellandrene (22.84%), whereas only 39 compounds were separated and identified by conventional SPME followed by GC-MS. The relative standard deviation (R.S.D.) values of less than 10% show that the proposed method has good repeatability. The result show that MD-SPME, followed by GC-MS, is a simple, rapid, solvent-free method for the determination of volatile compounds in ginger.     

Validation of an ELISA method for screening methadone in postmortem blood

In this study, we evaluate Venture Labs' enzyme-linked immunosorbent assay (ELISA) for the detection of methadone in postmortem specimens. Sixty-one postmortem specimens that previously screened positive for methadone along with 59 specimens which screened negative for methadone were included. All specimens were screened using the Venture Labs methadone assay in conjunction with a liquid-liquid basic extraction and gas chromatographic-mass spectrometric (GC-MS) analysis. All cases screening positive by either method were confirmed for methadone and its metabolite 2-ethylidene-1,5-dimethyl- 3,3-diphenylpyrrolidine by a solid-phase extraction utilizing deuterated internal standards and GC-MS-SIM. Twenty-four postmortem samples that screened negative by both methods were also extracted and analyzed using the confirmation method to demonstrate the validity of both screening methods. The intra- and interassay precision for the ELISA method was evaluated at the cut-off concentration used for the analysis (50 ng/mL). True positives, true negatives, false positives, and false negatives were calculated for the ELISA results as compared to the GC-MS screening data. The Venture Labs methadone assay demonstrated a sensitivity of 96.7%+/-2.3% and a specificity of 98.3%+/-1.7% relative to the GC-MS method.     

干姜挥发油提取优化及GC-MS图谱研究

目的:优化千姜挥发油提取工艺,同时建立干姜挥发油GC-MS指纹图谱.方法:以挥发油得率为指标,采用正交设计,对加水量、超声时间、浸泡时间和提取时间进行优化,并采集GC-MS图谱.结果:确定加17倍量水,超声35 min,浸泡40 min,再提取8 h的效果最优,挥发油得率分别为1.89%,GC-MS图谱稳定、重复.结论:干姜挥发油经过提取优化可以保证得率,获得的GC-MS图谱稳定可靠,并鉴定出的49种化合物.     

GC-MS法同时测定中药材中29种农药残留量

目的建立一种可同时对29种有机氯、有机磷类农药残留量进行定量检测的方法。方法利用GC-MS技术,配合负化学源检测器,采用选择离子检测法(SIM)进行定量,以石油醚-丙酮混合溶剂为洗脱溶剂,样品通过Florisil硅土柱净化,选择环氧七氯为内标物。结果对48种中药材进行了检测;除敌敌畏、杀虫脒、磷丹及三唑磷外,其余农药的检测限都在0.2～15 g.kg-1之间;以9种中药材为例检测,大部分农药的回收率在70%～120%之间。结论该方法简单、快捷、经济,分析结果达到农残分析的要求,适合大批量样品的同时检测。     

Automated extraction of 11-nor-delta9-tetrahydrocannabinol carboxylic acid from urine samples using the ASPEC XL solid-phase extraction system

The analysis of 11-nor-delta9-tetrahydrocannabinol-carboxylic acid (THCCOOH, the major metabolite of cannabis) in urine with gas chromatography and mass spectrometry (GC-MS) and solid-phase extraction (SPE) sample preparation is well documented. Automated SPE sample preparation of THCCOOH in urine, although potentially advantageous, is to our knowledge poorly investigated. The objective of the present study was to develop and validate an automated SPE sample-preparation step using ASPEC XL suited for GC-MS confirmation analysis of THCCOOH in urine drug control. The recoveries showed that it was not possible to transfer the protocol for the manual SPE procedure with the vacuum manifold to the ASPEC XL without loss of recovery. Making the sample more lipophilic by adding 1 mL 2-propanol after hydrolysis to the urine sample in order to overcome the problem of surface adsorption of THCCOOH led to an extraction efficiency (77%) comparable to that reached with the vacuum manifold (84%). The reproducibility of the automated SPE procedure was better (coefficient of variation 5%) than that of the manual procedure (coefficient of variation 12%). The limit of detection was 1 ng/mL, and the limit of quantitation was 4 ng/mL. Precision at the 12.5-ng/mL level was as follows: mean, 12.4 and coefficient of variation, 3.0%. Potential carryover was evaluated, but a carryover effect could not be detected. It was concluded that the proposed method is suited for GC-MS confirmation urinalysis of THCCOOH for prisons and detoxification centers.