吐温-80增敏同步荧光法检测蔬菜中二甲菌核利残留

Determination of Pythium Residues in Vegetables by Tween-80 Sensitized Synchronous Fluorescence

基于表面活性剂可增强二甲菌核利荧光强度,建立同步荧光分光光度法测定蔬菜中二甲菌核利残留量。对波长差进行了优化;讨论了溶剂种类、缓冲液的种类、用量及pH值等因素对二甲菌核利荧光强度的影响;应用正交实验对提取剂种类、用量、超声时间进行优化。选择甲醇做溶剂和提取剂,质量浓度为4.29g.L^-1吐温-80做表面活性剂。在0.14~3.00μg.mL^-1范围内,二甲菌核利浓度与荧光强度线性关系良好,检出限为0.1056mg.kg^-1,回收率为82.63~99.77%,RSD为0.16~0.61%。

Synchronous fluorescence method for determining pythium residues in vegetables based on surfactants sensitization was developed. The wavelength difference (Δλ) was selected. The effect of the solvent type, the type and amount of buffer, pH on the fluorescence intensity was discussed. The type and dosage of the extractant, the ultrasonic time were optimized by orthogonal test. Methanol was used as solvent and extractant. Tween-80 (4.29 g.L^-1) was used as the surfactant. In the range of 0.14 to 3.00 μg.mL^-1, the linear relationship between the concentration of pythium and its fluorescence intensity was good, and the detection limit was 0.105 6 mg.kg^-1. The recovery were 82.63 to 99.77%, RSD was 0.16 to 0.61%. The new method can be used to determine pythium residues in vegetables.