应助达人

Determination of residues of furalaxyl and metalaxyl in nutrient solution, peat compost and soil samples by gas chromatography


David J. Caverly and John Unwin

Rapid and sensitive techniques for the determination of residues of the fungicides furalaxyl and metalaxyl in agricultural samples are described. Air-dried soils and peat composts are extracted with acetone in a Soxhlet apparatus; the extract is applied directly to the gas chromatograph and detected using a nitrogen-selective detector. Plants are macerated with acetone and, after filtration and dilution with water, partitioned with chloroform; nutrient solutions are similarly extracted with chloroform. The extracts are subjected to gas chromatography after removal of chloroform and dissolution in acetone. Recoveries are generally better than 80% with detection limits of 0.5 mg kg^–1 for peat, 0.1 mg kg^–1 for soils and plants and 0.02 mg kg^–1 for nutrient solutions.

请问农产品中的这个东西能否准确测定？

应助达人

我们丁硫克百威的回收正常（按公式计算后）。

好像不稳定啊？

应助达人

主要是丁硫克百威可能会转化成克百威和三羟基克百威，看日本的方法好像是把丁硫克百威、克百威、呋线威和丙硫克百威都转化为三羟基克百威来检测的。

应助达人

呋菌胺

英文通用名称：Methfuroxam
英文商品名称：Furavax;Trivax；中文商品名称：三甲呋菌胺
英文化学名称：2,4,5-Trimethyl-N-phenyl-3-furancarboxamide
分子式：C14H15NO2 分子量：229.30


CAS编码：28730-17-8

性质：白色固体。大鼠急性经口LD501470～4300mg/kg。
主要用于禾谷类作物种子处理，防治腥黑粉菌属和黑粉菌属菌引起的病害。通常与抑霉唑、噻菌灵制成混剂使用。

检测仪器:LCMSMS

A simple and sensitive method was developed and validated for the simultaneous determination of 103 pesticide residues in tea by LC-MS/MS. For the analysis of the pesticide with polarity, thermal lability or low volatility, this LC-MS/MS method has an advantage over GC. In this work, residual pesticides were extracted from the tea sample with ACN and then purified using Carb-NH2 SPE cartridges. Using the multiple reaction monitoring mode, the pesticides were quantified and identified by the most abundant and characteristic fragment ions. The recoveries obtained for each pesticide ranged between 65 and 114% at three spiked concentration levels. The intra-day precisions were lower than 19.6%. Good linear relationships were observed with the correlation coefficients r2 >0.996 for all analytes. The established method was successfully applied to the determination of pesticide residues in real tea samples.