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1.
建立了超声波辅助提取-气相色谱法同时检测湿毒清片中14种有机磷农药残留的方法。样品采用乙酸乙酯超声提取,通过石墨化炭黑净化,采用气相色谱-火焰光度法(GC-FPD)进行检测。除乐果以外,13种有机磷农药于0.1mg/kg、0.5mg/kg两个加标水平的回收率在80.4%~114.5%之间,相对标准偏差为0.6%~12.4%。方法满足农残分析的要求,可用于湿毒清片中14种有机磷农药残留量的检测。  相似文献   

2.
建立了果实类中药材中多种有机磷农药残留同时测定的方法,并对影响提取、净化、检测效率的因素进行优化。样品用乙酸乙酯提取,凝胶渗透色谱收集9~15 min流分,ENVI-Carb固相萃取柱净化,DB-1701毛细管色谱柱分离,火焰光度检测器检测,外标法定量。在优化条件下,20种有机磷农药在0.01~2.0mg/L范围内具有良好的线性关系,相关系数为0.996 6~0.999 5,检出限(S/N=3)为0.66~5.78μg/kg。3个加标水平下的平均回收率为80.2%~109.9%,相对标准偏差为2.3%~13%。该方法操作简便、准确、净化效果好,可满足果实类中药材中多种有机磷农药残留的同时测定要求。  相似文献   

3.
建立了4种植物提取物中39种有机磷类农药残留的GC-MS/MS分析方法。试样经1%乙酸乙腈提取,应用QuEChERS技术净化,测定蔓越橘提取物、石榴皮提取物、橄榄叶提取物和问荆提取物中39种有机磷农药残留。39种有机磷农药在0.005~1.0 mg/L范围内线性关系良好,相关系数(r2)均大于0.9915;加标回收率为62.0%~126.4%;相对标准偏差(RSD)在2.4%~18%之间;方法的检出限(LOD)为0.2~3.2μg/kg,定量限(LOQ)为0.5~10.0μg/kg。方法适用于蔓越橘等4种植物提取物中39种有机磷类农药残留的定性、定量分析。  相似文献   

4.
通过优化提取溶剂和提取方式,确定土壤中的福美胂残留采用苯振荡离心一体提取,苹果用甲苯均质提取,采用高效液相色谱,建立了苹果和土壤中福美胂残留的直接检测方法。采用外标法定量,在0.1~5.0 mg/L范围内,具有良好的线性关系,相关系数为0.9996。当土壤中添加量为0.2~1.0 mg/kg时,回收率在86.0%~103.5%之间,RSD在2.9%~5.0%之间,定量限为0.1 mg/kg;当苹果中的添加量在0.3~2.0 mg/kg时,回收率在91.0%~95.2%范围内,RSD在1.4%~4.7%之间,定量限为0.3 mg/kg。方法应用于实际土壤和苹果样品的福美胂残留量检测,符合农药残留检测的要求。  相似文献   

5.
采用基质固相分散(MSPD)代替液液分配和固相萃取,从蔬菜水果中提取、净化10种常用杀菌剂农药残留,用C18硅胶交联剂作为固相吸附剂,乙酸乙酯作为洗脱液,用HPLC/PDA和LC-MS进行分析检测。10种杀菌剂在0.5~5 mg/kg含量的添加回收率在65%~110%之间,相对标准偏差小于10%,使用HPLC、PDA和LC-MS的检出限分别在0.02~0.2 mg/kg和0.002~0.01 mg/kg之间。该方法节省溶剂,提取和净化一步完成,适用于新鲜水果和蔬菜中10种杀菌剂的残留分析。  相似文献   

6.
建立了以凝胶渗透色谱(GPC)和固相萃取(SPE)净化、气相色谱-质谱(GC-MS)法同时测定紫皮石斛中10种有机磷农药残留的方法。样品用乙腈超声提取,提取液经GPC去除类脂杂质和大分子物质,后经Envi-Carb/NH2固相萃取柱净化,选择离子(SIM)监测模式检测,外标法定量。在26min内10种农药得到很好的分离,农药残留量在0.02~0.5μg/mL,方法的线性良好,相关系数为0.997 3~0.999 9,农药加标浓度为0.05mg/kg和0.2mg/kg时,加标回收率在70.4%~115.8%,相对标准偏差在2.8%~9.6%,满足国家标准要求,检出限为0.005 2~0.011mg/kg。方法简便、快速、灵敏、准确,能够运用于石斛中多组分有机磷农药残留的定性和定量分析。  相似文献   

7.
将气相色谱-负离子化学源质谱法(GC-NCIMS)应用于牛奶饮品和奶粉中19种有机磷农药残留的同时分析。牛奶饮品和奶粉经乙腈提取剂超声提取、Florisil硅藻土和中性氧化铝双净化剂同时净化及正己烷-乙酸乙酯(体积比1∶1)混合洗脱剂洗脱后,以三苯基磷酸酯为内标物,采用GC-NCI MS的选择离子监测方式(SIM)定性与定量分析。当牛奶饮品和奶粉的加标浓度水平为20、100、500μg/kg时,平均加标回收率为64.5%~129%,相对标准偏差为2%~20%;除喹硫磷的方法检出限(MDL)为2.4μg/kg外,其余18种有机磷农药的MDL均小于1.0μg/kg;线性范围为10~500μg/kg,相关系数均大于0.9988,此分析方法成功地应用于牛奶饮品和奶粉中多种痕量有机磷农药残留的分析。  相似文献   

8.
毛细管气相色谱法快速测定辣椒中7种有机磷农药残留   总被引:3,自引:3,他引:0  
建立同时测定辣椒中7种有机磷农药残留量的方法。用乙酸乙酯提取,经旋转浓缩后用丙酮定容,直接进样,以HP-1701毛细管色谱柱分离,火焰光度检测器测定。结果表明,7种农药在10min内可很好地分离。样品加标回收率为80.8%~108.8%,方法的相对标准偏差为2.0%~10.7%(n=5)。7种农药的检出限为1.5~7.0μg/kg。  相似文献   

9.
建立了杀虫剂灭幼脲在甘蓝及其土壤中残留量的高效液相色谱检测方法。样品经提取和固相萃取(SPE)小柱净化后进行测定,灭幼脲的回收率为77.1%~81.6%,变异系数在4.3%~9.7%之间。残留动态研究表明,灭幼脲在甘蓝及其土壤中消解的半衰期分别为4~6 d和15~16 d;以20 g制剂/亩的剂量(最高推荐剂量)施药14d后收获时,甘蓝中最高残留量为0.38 mg/kg,土壤中最高残留量为0.28 mg/kg。  相似文献   

10.
采用改良的QuEChERS法提取,气相色谱-火焰光度检测(GC-FPD),建立了同时测定茶叶中敌敌畏、乐果、毒死蜱、水胺硫磷和三唑磷5种有机磷农药(OPPs)残留的分析方法。茶叶样品经改良的QuEChERS方法进行前处理,经GC-FPD检测,基质外标法定量。在最优条件下,上述5种有机磷农药的线性范围分别为:1.8~100μg/L、2.0~200μg/L、0.5~100μg/L、1.6~200μ/L和1.2~200μg/L,相关系数r均大于0.998。在2~50μg/L添加水平范围内,5种目标农药的平均回收率在80%~108.3%之间,相对标准偏差(RSD,n=5)为2.58%~7.31%,检出限(S/N=3)在0.608~4.420μg/kg之间,定量限(S/N=10)在3.448~10.736μg/kg之间。该方法检出限低、操作简单、分析速度快,适用于茶叶中上述5种有机磷农药残留的同时检测。  相似文献   

11.
对氨基酚络合萃取机理的探讨   总被引:1,自引:0,他引:1  
魏凤玉  韦洪屹 《应用化学》2005,22(10):1155-0
对氨基酚络合萃取机理的探讨;对氨基酚; 络合萃取; 萃取机理; 萃取反应热  相似文献   

12.
Open-vessel focused microwave (FMW) extraction with a purely aqueous carbonate solution was used for the extraction of chlorophenols from various solid matrices. After SPE on C18-bonded silica, the analytes were determined as such by LC-UV or, as their acetyl derivatives, by GC-ECD. The FMW aqueous extraction is efficient and rapid and no organic solvents are used. PCP was detected in several solid samples, with recoveries of 101-115% (RSD, 2-4%) relative to Soxhlet extraction. Similar recoveries were obtained for the other chlorophenols for spiked samples.  相似文献   

13.
超声辅助液液萃取法提取烟用香精成分的研究   总被引:1,自引:0,他引:1  
采用超声辅助液液萃取法(ULLE)提取某品牌烟用香精成分,GC-MS对其进行分析,研究了不同萃取剂、萃取时间和萃取温度对分析结果的影响,初步确定了最佳条件为:以二氯甲烷为萃取剂,饱和NaCl溶液作水相,室温下超声萃取5 min.又分别与同时蒸馏萃取法(SDE)和传统的液液萃取法(LLE)作以比较,对ULLE法和SDE法鉴定出的化学成分、重现性和定量值进行了对比.结果表明:超声辅助液液萃取具有操作简便、快速、节能、萃取效率高、重现性好等特点,适合于烟用香精成分的提取.  相似文献   

14.
安静  渠星宇  乔金锁 《化学教育》2019,40(14):41-45
通过学生分组,采用溶剂提取法,超声提取法和微波提取法等提取方法,测定了小米、糜子、青稞、荞麦和高梁等杂粮中黄酮含量,结果表明5种杂粮中,青稞中总黄酮的含量最高。该综合实验能够锻炼大学生运用所学实验技术解决实际问题的能力,适合作为高年级本科综合实验项目开设。  相似文献   

15.
中草药化学成分提取新技术   总被引:14,自引:0,他引:14  
介绍五种提取新技术棗微波萃取技术、超临界二氧化碳萃取技术、超声波提取技术、半仿生提取技术和酶法的原理和特点,以及这些新技术近年来在中草药化学成分提取工艺中的研究应用现状,并展望了它们的应用前景。  相似文献   

16.
Extraction and quantification of herbicide residues from soil are important in understanding the behaviour of persistent herbicides. This research investigated extraction and clean-up methods for imidazolinone herbicides from soil and soil amended with organic material. A series of solvent mixes, pH conditions and sorbents was tested. Across three imidazolinone herbicides: imazapyr, imazethapyr and imazaquin, 0.5 M NaOH extraction gave greater than 90% recovery from soil samples; however, 0.5 M NaOH:MeOH (80:20) resulted in higher recovery for imazaquin, but not for the other two herbicides. Of the sorbents tested, the use of chromatographic mode sequencing using C18 and SCX sorbents provided consistent high (>85%) recovery of all three herbicides from soil and separation of the herbicides from other soil components by high performance liquid chromatography (HPLC). These two methods will allow high recovery of these imidazolinone herbicides from soil and have the ability to detect these herbicides without interference from other soil components.  相似文献   

17.
Supercritical fluid extraction (SFE) provides for the first time a viable option to conventional and widely used Soxhlet extraction. The ability to change the solvating power of a single supercritical fluid by changing its density is an exceedingly attractive feature. An environmentally safe alternative such as supercritical carbon dioxide to organochlorine solvents which are widely used today in many government and industrial analytical laboratories for sample preparation is desirable. SFE may also constitute a viable alternative to other popular sample preparation techniques such as liquid-liquid extraction, solid phase extraction and purge/trap. Much research, however, must be done in order to understand, optimize and apply this technology. For example, (a) automation of extraction, (b) matrix effects, (c) new fluids/modifiers/additives, (d) trapping efficiency, (e) recovery of extracted analytes, and (f) extraction kinetics are some areas which need a greater understanding. This review is concerned with many of these topics as they relate to trace organic analysis wherein SFE is the primary sample preparation technique.  相似文献   

18.
Naturally contaminated corn samples of different origin were extracted using two conventional techniques (blending and shaking) and three alternative approaches (ultrasonic extraction, accelerated solvent extraction, and microwave-assisted extraction). Use of the same extraction mixture for all trials enabled the efficiency of the various extraction techniques to be compared. Extracts were filtered and directly analyzed by LC–ESI–MS, without further clean-up. The yield from the alternative extraction techniques showed efficiency to be higher than for conventional techniques. In particular, microwave-assisted extraction was slightly superior to other techniques.  相似文献   

19.
The optimised BCR sequential extraction procedure and a 4 h 1 mol L−1 HCl partial extraction have been performed on the NIST 2711 reference material for a suite of 12 elements (Cd, Sb, Pb, Al, Cr, Mn, Fe, Co, Ni, Cu, Zn, As) using magnetic sector ICP-MS. A pseudo-total aqua regia digest of NIST 2711 has also been undertaken for quality assurance purposes, and comparison of the sum of the four BCR fractions, which included an aqua regia digest on the residue, with the pseudo-total aqua regia digest has been used to assess the accuracy of the BCR partitioning approach. As a result of this work, discrepancies between previous studies about BCR partitioning of elements in NIST 2711 have been discussed and an increase in confidence about the use of BCR partitioning scheme on seven elements (Cd, Pb, Al, Mn, Fe, Cu, Zn) in this standard material has been obtained. On the other hand, BCR partitioning for Sb, Cr, Co, Ni and As has been provided for the first time. Partial extraction results are also reported for the same 12 elements analysed by the optimised BCR procedure, with the partial extraction results exhibiting a strong correlation with the sum of the three labile steps of the BCR procedure.  相似文献   

20.
Ali Liazid  Jamal Brigui 《Talanta》2007,71(2):976-980
The stability of Ochratoxin A during its extraction using different extraction techniques has been evaluated. Microwave-assisted extraction and pressurised liquid extraction, in addition to two other reference methods of extraction, i.e. ultrasound-assisted and magnetic stirring-assisted extraction, were evaluated. The effect of extraction temperature using the cited techniques was checked.The results show that Ochratoxin A can be extracted using microwave-assisted extraction at temperatures up to 150 °C without degradation. Pressurised liquid extraction can be used at temperatures up to 100 °C, for extraction times of less than 30 min. Further, both ultrasound-assisted extraction and magnetic stirring extraction can be applied at temperatures up to 65 °C.High-performance liquid chromatography combined with fluorescence detection using a Chromolith RP-18e column at a flow rate of 5 mL min−1 was used to quantify the Ochratoxin A. The retention time for the Ochratoxin A was 1.3 min. The limits of detection (LOD) and of quantification (LOQ) were 0.03 and 0.10 μg L−1, respectively.  相似文献   

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