以己烯雌酚为替代模板,利用整体材料的"原位"合成技术制备了分子印迹聚合物,并将其作为固相萃取搅拌棒的涂层(MIP-SBSE)制备了新的搅拌棒。详细考察了分子印迹聚合物制备条件中模板分子及功能单体用量对MIP-SBSE选择性萃取性能的影响,同时利用元素分析、扫描电镜和红外光谱对聚合物进行表征。以双烯雌酚(DS)和己烷雌酚(HS)为目标化合物,将MIP-SBSE与高效液相色谱-二极管阵列检测器联用,建立起复杂样品中DS和HS的分离分析方法。考察了吸附和解吸时间、解吸溶剂、离子强度和样品pH值等萃取条件对MIP-SBSE选择性萃取性能的影响。结果表明,在最佳萃取条件下,MIP-SBSE对DS和HS具有较高的选择性萃取性能,线性范围分别为1.0~400.0μg/L和5.0~400.0μg/L,利用氮吹再定容的方法,对DS和HS的检出限(S/N=3)分别可低至0.04和0.14μg/L。在对实际污水、蜂蜜和牛尿样品的分析中取得了良好的加标回收率,其值为61.3%~120%。所建方法具有简便、高选择性和灵敏等特点,可用于复杂样品中双烯雌酚和己烷雌酚的分析监测。
A new stir bar sorptive extraction(SBSE) coating based on molecularly imprinted polymer(MIP) with diethylstilbestrol as replaced template molecule was prepared.The influences of the contents of template molecule and monomer in the polymerization mixture on the extraction performance of MIP-SBSE were investigated thoroughly.The MIP was characterized by elemental analysis,scanning electron microscopy and infrared spectroscopy.In order to evaluate the usability of the new coating,the MIP-SBSE was combined with high performance liquid chromatography(HPLC) and diode array detector(DAD) with dienestrol(DS) and hexestrol(HS) as detected solutes.To achieve optimally selective extraction performance for DS and HS,several parameters,including extraction and desorption times,desorption solvent,ionic strength and pH value in sample matrix were investigated.The results showed that under the optimized experimental conditions,the present method has high selectivity and sensitivity.When drying-redissolving procedure was taken during sample preparation,the limits of detection for DS and HS were as low as 0.04 μ g/L and 0.14 μ g/L,respectively.Good linearities were obtained for analytes with the correlation coefficients(R 2) above 0.99.Finally,the proposed method was successfully applied to the determination of DS and HS in wastewater,honey and cow urine samples.The recoveries of spiked target compounds in real samples ranged from 61.3%to 120%.The developed method is simple,selective,sensitive and applicable for the analysis of trace DS and HS in complicated samples.