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1.
生物材料中克伦特罗的气相色谱-质谱法测定   总被引:20,自引:3,他引:17       下载免费PDF全文
建立了生物材料中克伦特罗 (clenbuterol)的气相色谱 -质谱测定方法 ;大白鼠喂食克伦特罗获得阳性生物材料 ,生物材料中克伦特罗经0.01mol/L盐酸溶液提取 ,乙醚脱脂净化 ,乙酸乙酯提取后蒸发至干 ,用乙醇溶解后加样到氧化铝柱上 ,用0.01mol/L盐酸溶液洗脱 ,蒸发至干后 ,用BSTFA(双三甲基硅烷基三氟乙酰胺 ) +1 % (φ)TMCS(三甲基氯硅烷 )衍生 ,采用GC -MS进行测定 ,外标法定量 ;试验表明 ,生物材料中添加0.056×10 -6~0.54×10 -6(w)含量水平的克伦特罗 ,方法回收率在89 %~107 % ,相对标准偏差为7.3 %~16 % ,线性相关系数r为0.998,克伦特罗的检出限为2.0×10-9(w)。  相似文献   

2.
研究了用液-液萃取和固相萃取两种方法同时分离饲料中克伦特罗和沙丁胺醇.液.液萃取法中,采用乙酸乙酯 正己烷 异丙醇混合溶剂,克伦特罗和沙丁胺醇萃取率分别可达85.20%、83.00%:固相萃取法中,采用Amberlite XAD-2大孔吸附树脂,效果较液.液萃取更好。萃取率为91.25%和86.10%.两种分离方法用于饲料中克伦特罗和沙丁胺醇的测定。结果满意.  相似文献   

3.
蜂蜜中咖啡因含量的液相色谱法测定   总被引:1,自引:0,他引:1  
介绍了用液相色谱法测定蜂蜜中咖啡因含量 ,样品在碱性条件下经氯仿萃取 ,萃取液用HPLC进行检测 ,其线性范围在0.010×10 -6~10×10 -6(w) ,定量下限为0.010×10 -6(w) ,回收率>80% ,相对标准偏差<2%。  相似文献   

4.
固相萃取-离子色谱法分析胺液中的热稳态盐离子组成   总被引:3,自引:0,他引:3  
建立了固相萃取(SPE)-离子色谱(IC)法测定脱硫胺液中热稳态盐(HSS)离子的分析方法,优化了萃取上样量、流速、解吸溶剂等条件。Cl-、2-4SO、SCN-、HCOO-、H3CCOO-和H3CH2CCOO-的检出限为0.02×10-6(w),0.1×10-6(w),0.4×10-6(w),0.002×10-6(w),0.15×10-6(w),0.4×10-6(w),相对标准偏差(RSD,n=6)为3.2%~7.6%。同时建立了离子交换-容量法分析胺液中的热稳态盐分析方法,对离子交换和固相萃取两种处理样品的方法进行了对比,SPE法检出限低而且重复性好。采用SPE-IC和离子交换-容量法,对实际胺液样品进行分析对比,实验结果表明当胺液中HSS的含量大于1%时,采用容量法简单快速;当HSS的含量小于1%时,采用固相微萃取法-离子交换法比较准确。  相似文献   

5.
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。  相似文献   

6.
采用凝胶渗透净化技术,建立了用高效液相色谱串联质谱法同时测定动物源肝脏中克伦特罗、沙丁胺醇、莱克多巴胺、特步它林残留量的方法。样品经β-葡萄糖苷酸酶水解后,用乙酸铵溶液提取,MCX固相萃取柱和全自动凝胶渗透净化色谱仪净化,采用选择离子监控模式(SIM)检测,内标法定量。克伦特罗在0.1~10 ng/mL、莱克多巴胺、沙丁胺醇、特布他林在1~100 ng/mL质量浓度范围内呈良好的线性关系,相关系数(r2)均大于0.999;方法的检出限和定量限分别在0.003~0.02μg/kg和0.009~0.06μg/kg之间,方法的回收率为94.7%~106.1%,相对标准偏差小于7.8%。适用于动物肝脏中克伦特罗、沙丁胺醇、莱克多巴胺、特步它林的确认和定量检测。  相似文献   

7.
茶叶中噻嗪酮残留量的GC-MS测定   总被引:8,自引:0,他引:8  
采用样品处理的微量化学法和固相萃取技术,建立了茶叶中噻嗪酮残留量的GC -MS测定方法 ;用丙酮 -正己烷 (体积比1∶1)萃取 ,活性碳和中性氧化铝小柱净化 ,净化液用GC -MS测定,外标法定量 ;方法回收率在88%~109 %之间,相对标准偏差为2 %~4 %,测定限为0.010×10-6(w);该法快速、灵敏、准确 ,各项技术指标均满足残留量检测的要求。  相似文献   

8.
稻谷中吡虫啉农药残留量的固相萃取高效液相色谱测定   总被引:43,自引:2,他引:41  
介绍了用高效液相色谱法测定稻谷中吡虫啉农药残留量的方法 ,样品经乙腈超声提取 ,固相萃取小柱快速净化提取物 ,HPLC -UV分离测定 ,外标法定量 ,方法的定量下限为0.005×10-6(w) ,回收率>80 % ,相对标准偏差<7 %。  相似文献   

9.
固相萃取-高效液相色谱法同时测定克伦特罗和沙丁胺醇   总被引:8,自引:0,他引:8  
提出用固相萃取 -高效液相色谱法同时测定饲料中微量克伦特罗和沙丁胺醇的新方法。选用 Dikma Diamonsil C18-ODS分析柱 (2 0 0× 4.6mm,5μm) ,乙腈 -0 .0 1mol/ L KH2 PO4 (p H 3 .0 )作流动相 ,应用波长编程进行检测。克伦特罗和沙丁胺醇的线性范围为 0 .1~ 1 0 0μg/ m L,相关系数分别为 0 .99999和 0 .99977,检出限分别为0 .3 1 ng/ m L和 0 .2 4ng/ m L ,回收率分别为 91 .2 %~ 92 .0 %和 91 .9%~ 93 .0 % ,相对标准偏差分别是 1 .2 0 %~ 2 .0 5%和 1 .2 9%~ 2 .51 %。  相似文献   

10.
本实验提出:在盐酸-碘化钾-抗坏血酸(V.C)介质中,用甲基异丁基甲酮(MIBK)同时萃取银、镉、铊,不加基体改进剂,使用自制的简易石墨炉平台连续测定。该法测定银、镉、铊的灵敏度分别是:3.1×10~(12)克/1%吸收、6.1×  相似文献   

11.
In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.  相似文献   

12.
KMnO4-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields.  相似文献   

13.
The review contains a concise historical account and information on the most significant researches undertaken by the staff at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences on the Chemistry of Heterocyclic Compounds. Dedicated to Academician of the Russian Academy of Sciences B. A. Trofimov on his 70th jubilee. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1443–1502, October, 2008.  相似文献   

14.
Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.  相似文献   

15.
A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.  相似文献   

16.
The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp3)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp2)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp2)?H and aliphatic 1,5- and 1,6-C(sp3)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp3)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp2)?H insertion.  相似文献   

17.
The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines.  相似文献   

18.
N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).  相似文献   

19.
20.
An efficient approach to the synthesis of highly congested di, penta and hexacyclic pyrazoles as well as imidazole fragment containing novel heterocyclic molecule has been developed through a carbanion induced transformation of suitably functionalized 2H-pyran-2-ones, benzo[h]chromene and thiochromeno[4,3-b]pyrans. Due to the presence of fluorescence, we report their prime application metal sensor as off/on switching in ferric ions.  相似文献   

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