离子色谱法分析土壤中的矮壮素和缩节胺

Analysis of Chlorocholine Chloride and Mepiquat Chloride in Soil by IC

建立了离子交换色谱–直接电导法同时测定土壤中矮壮素和缩节胺残留的分析方法。样品经磨碎超声提取后,用固相萃取(SPE)柱祛除蛋白质,过0.22μm过滤膜,进样检测。考察了不同的阳离子色谱柱SH–CC–1,SH–CC–2,SH–CC–3及其不同的淋洗液对矮壮素、缩节胺的保留时间和分离度的影响。确定了最佳色谱条件:SH–CC–3阳离子色谱柱;直接电导检测;淋洗液选用3.0 mmol/L甲烷磺酸,流速为1.0 mL/min;柱温:40℃;进样量:100μL。在此条件下,矮壮素及缩节胺在0.20～20.0 mg/kg范围内,线性相关系数r均大于0.999,矮壮素和缩节胺的检出限(S/N=3)分别为0.070,0.073 mg/kg,加标回收率分别为86.0%～93.8%,84.9%～93.2%,测定结果的相对标准偏差小于4.2%。方法选择性好,灵敏度高,抗干扰能力强,适用于检测土壤中矮壮素和缩节胺。

A comprehensive analytical method for the simultaneous determination of chlorocholine chloride（CQ） and mepiquat chloride（MQ） residues in soil by ion exchange chromatography （IC） with direct conductivity detection was developed. After grind and ultrasonic extration, sample were cleaned by SPE and filtered by 0.22μm filter membrane. The chromatographic separation was performed on SH-CC-1, SH-CC-2 and SH-CC-3 cation exchange column with respective eluent. The effects of chromatographic column on the separation and retention factors of CQ and MQ were investigated. The optimized chromatographic conditions for the determination of MQ and CQ were as follows ： eluent solution was 3.0 mmol/L sulfonic acid at flow rate of 1,0 mL/min, with a column temperatures of 40℃, and SH-CC-3 cation exchange column, sample loop was 100 μ L. Under the optimal conditions, the calibration graph of peak area for MQ and CQ had good linear in 0.20-20.0 mg/kg（r≥ 0.999）. The limits of determination（S/N=3） for CQ and MQ were 0.070 and 0.073 mg / kg, respectively. The recoveries of CQ and MQ added standard were 86.0%-93.8% and 84.9%- 93.2%, respectively. The RSD of CQ and MQ determination results was 1.76%-4.1%. The method has good selectivity, accuracy and strong anti-interference ability, it is suitable for residues determination of MQ and CQ in soil.