介孔分子印迹聚合物分离分析奶粉中的三聚氰胺

以灭蝇胺为虚拟模板分子,采用溶胶凝胶技术制备灭蝇胺介孔分子印迹聚合物(MIP)。将MIP作为固相萃取吸附剂,与高效液相色谱联用检测奶粉样品中的三聚氰胺。对该聚合物进行了吸附等温线测定以及Scatchard分析,结果表明分子印迹聚合物对三聚氰胺有两种结合方式。计算得到的最大表观结合量(Qmax)和平衡解离常数(Kd)分别为:Qmax1=14.96 mg/g,Kd1=1.85 mg/L;Qmax2=26.16 mg/g,Kd2=27.03 mg/L。最后应用合成的MIP对2 g奶粉样品提取液中痕量三聚氰胺进行净化和富集,回收率为94.73%~98.56%,相对标准偏差RSD为3.2%,检出限为0.015μg/g。此方法快速、选择性高,为三聚氰胺的残留分析开辟了一条新途径。 

Separation and analysis of melamine in milk powder by mesoporous molecular imprinted polymers

Mesoporous molecular imprinted polymers( MIP) was prepared by Sol- Gel technique using cyromazine as virtual template molecule. The MIPs used as solid phase extraction adsorbents were coupled with high performance liquid chromatography( HPLC) to detect melamine in milk powder samples. The results of isothermal absorption experiment and Scatchard analysis showed that there were two kinds of binding sites. By calculating,the values of the apparent maximum absorption capacity Qmaxand the dissociation constant Kdwere as follows:Qmax1= 14.96 mg / g,Kd1= 1.85 mg / L,Qmax2= 26.16 mg / g,Kd2= 27.03 mg / L. The melamine in 2 g milk powder samples was purified and enriched by MIP. The recovery of melamine was between 94.73% and 98.56%,relative standard deviation( RSD) was 3.2%,and the detection limit was 0.015 μg / g. This method was rapid and high selectivity,and provided a new way to analyzing residue melamine.