固相萃取_高效[url=https://insevent.instrument.com.cn/t/5p]液相色谱法测定河水中的多菌灵含量[/url]
高效[url=https://insevent.instrument.com.cn/t/5p]液相色谱法测定人参中多菌灵农药残留含量[/url]

你好，我要怎样才能防止乳化呢？

适当增大溶剂量，加入石油醚的同时加入饱和氯化钠溶液。振荡充分即可，别太久。一旦乳化，加溶剂或者加盐破乳。

Determination of carbendazim, thiabendazole, and o-phenylphenol residues in lemons by HPLC following sample clean-up by ion-pairing
Konstantinos P. Prousalis, et al.;
Analytical and Bioanalytical Chemistry, Volume 379, Number 3/2004: 458-463

Abstract:
An efficient analytical method is presented involving effective sample clean-up with solid-phase extraction and HPLC-UV analysis for the simultaneous determination of carbendazim, thiabendazole, and o-phenylphenol residues in lemons. Sample preparation involves extraction with acetonitrile acidified with trifluoroacetic acid and an ethyl acetate/petroleum ether mixture. Purification of the crude extract was carried out with liquid–liquid partitioning after addition of an aqueous ammonia solution. Final clean-up was performed on polymeric reversed-phase cartridges pretreated with sodium dodecyl sulfate. Chromatographic analysis was performed on a reversed-phase HPLC column isocratically eluted with an acetonitrile/water/ammonia mixture and UV detection at 254 nm. The chromatographic method is repeatable, reproducible, and sensitive. Fungicide recoveries from lemon samples fortified at levels of 5 and 1 mg kg^–1 were 81–85% for carbendazim, 96–98% for thiabendazole, and 81–106% for o-phenylphenol with coefficients of variation of 2.5–7.4%. Detection limits for carbendazim, thiabendazole, and o-phenylphenol in lemons were 0.21, 0.27, and 0.51 mg kg^–1, respectively.
http://www.springerlink.com/content/mab4q3yc1bkkeff4/

Determination of carbendazim, thiabendazole and thiophanate-methyl in banana (Musa acuminata) samples imported to Italy
Food Chemistry,Volume 87, Issue 3, September 2004,383-386
Attilio Veneziano,et al.;

Abstract:
The occurrence of benzimidazole fungicides (benomyl and its metabolites carbendazim, thiabendazole and thiophanate-methyl) in 50 banana samples imported to Italy from Ecuador, Panama and Costa Rica during 2002–2003 was investigated. In 11 samples, thiabendazole was found at concentrations ranging from 0.050 to 2.510 mg/kg. In five samples, carbendazim was found at concentrations ranging from 0.140 to 1.100 mg/kg, whereas thiophanate-methyl was not detected in any sample. Analysis was carried out using HPLC-DAD and positive samples were confirmed by GC–MS. Recoveries of carbendazim, thiabendazole and thiophanate-methyl at four fortification levels (0.5, 1.0, 2.5 and 4.0 mg/kg) were in the range 81–96% for carbendazim and thiabendazole and 63.2–69.8% for thiophanate-methyl. Only two samples contained carbendazim that exceeded the FAO/WHO Codex Alimentarius and the Italian Department of Health maximum residue limits.


http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6T6R-4BRSFK9-6&_user=10&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=4ea8d8b2f228f6214f6a0f5207b2df12

最近我也在做多菌灵的方法，貌似，多菌灵的单标做液相都是两个峰。流动相分别用甲醇：磷酸盐缓冲溶液（ph6.8)，甲醇：磷酸，甲醇：离子对试剂，甲醇：水这4种，比值都是40：60，信号是280nm，全部都出来2个峰，这是为什么？请问到底做多菌灵液相应该用哪种流动相最合适？才能防止甲基菌硫灵出现？

现在我们用LC-MSMS做多菌灵检测了，回收率很好

我用少量盐酸溶解多菌灵，然后用甲醇定容。再做标准曲线，流动相甲醇和水对半，只有一个峰。特征波长258nm

应助达人

可以考虑用液质做，前处理用已经提取，Qsechers方法净化，效果还是不错的