高效毛细管电泳法快速测定乳制品中三聚氰胺

建立高效毛细管电泳快速测定乳制品中三聚氰胺含量的方法。样品用100mmol/L 醋酸提取，以150mmol/L磷酸二氢钠为分离缓冲液，以未涂敷石英毛细管(20cm(有效长度)× 50μm)为分离柱，于235nm 波长处检测，采用峰面积外标法定量。实验研究缓冲溶液的浓度、分离溶液pH 值及样品前处理条件对三聚氰胺准确定量的影响。方法检出限为0.06mg/L，定量限为0.2mg/L，线性范围为0.2～200mg/L，线性相关系数r=0.9998。1.0、10mg/L 添加水平的平均加标回收率分别为93.0% 及84.3%。该方法简单快速，6min 之内即可完成一次样品分析(预清洗2min，分离4min)且试剂消耗少、环境友好及检测准确，适合于各类乳制品中三聚氰胺的常规测定。

High Performance Capillary Electrophoretic Determination of Melamine in Milk Products

A new method for the rapid determination of melamine in milk products by high performance capillary electrophoresis (HPCE) with diode array detection was established. Samples were extracted with 100 mmol/L acetic acid. The chromatographic separation was carried out in an uncoated fused-silica capillary 20 cm (effective length) ×50 μm] using 150 mmol/L NaH2PO3 as a separation buffer. Melamine was detected at 235 nm and quantified by peak-area external standard method. The effects of buffer concentration, running pH and sample pretreatment conditions on HPCE detection of melamine were investigated. The LOD and LOQ of the method were 0.06 (S/N = 3) and 0.2 mg/L (S/N = 10), respectively. The linear range was from 0.2 to 200 mg/L with a correlation coefficient of 0.9998. The average spiked recoveries of five replicates at two levels (1.0 and 10 mg/L) were 93.0% and 84.3%, respectively. The analysis could be completed within 6 min (2 min for rinsing plus 4 min for separation). The HPCE method is time- and solvent-saving, and environment-friendly, and has a good accuracy. Therefore, it can be used for the routine determination of melamine in milk products.