固相萃取-高效液相色谱法同时测定食用菌中多菌灵和噻菌灵残留量

Simultaneous Determination of Residual Amounts of Thiabendazole and Carbendazim in Edible Fungus by HPLC with Solid Phase Extraction

食用菌样品经乙酸乙酯提取、氮气吹干,0.05 mol·L^(-1)盐酸溶解后,经固相萃取小柱净化用液相色谱法测定。测定中采用Waters Symmetry C_(18)色谱柱为固定相以及磷酸盐缓冲溶液和乙腈(75+25)混合溶液作为流动相。用二极管阵列紫外检测器于288 nm波长处进行紫外检测,外标法定量。方法的检出限(3S/N)和测定下限(10S/N)依次为0.010 mg·L^(-1)和0.025 mg·L^(-1)。在4个不同的浓度水平对方法的回收率进行了试验,测得结果在72.0%～86.0%之间。测定值的相对标准偏差(n=6)均小于8.5%。

Residual amounts of thiabendazole （TBD） and carbendazim （CBD） were extracted ulltrasonically with ethylacetate from samples of edible fungus. The extract was evaporated to dryness by N2-blowing and the residue was dissolved in 0. 05 mol·L^-1 HCL TBD and CBD in dil. HCl solution was then purified by SPE. The Waters Symmetry C18 column was used as stationary phase and a mixture of phosphate buffer solution and acetonitrile （mixed in the ratio of 75＋25 by volume） was used as mobile phase. UV-detection was made using diode array detector at the wavelength of 288 nm, and external standard were used for quantification. Limit of detection （3S/N） and lower limit of determination （10S/N） of the methd were found to be 0. 010 mg·L^-1 and 0. 025 mg·L^-1 respectively for both bactericides. Tests for recovery and precision were made at 4 different concentration levels, and values of recovery found were in the range of 72. 0%--86. 0% with values of RSD＇s （n=6） less than 8.5%.