基于场放大进样富集的微流控芯片-激光诱导荧光法检测奶制品中的β-酪啡肽

Separation and determination of β-casomorphins in dairy foods by microchip capillary electrophoresis coupled with laser induced fluorescence detection based on field amplified sample stacking

基于微流控芯片-激光诱导荧光分析技术,探讨了奶酪中两种β-酪啡肽(β-CM-5和β-CM-7)的场放大进样富集和检测。采用10 mmol/L硼酸-硼砂溶液(pH8.7)作为衍生缓冲液,5 mmol/L硼砂溶液(pH8.9)作为样品缓冲液,进样10s,60 mmol/L硼砂溶液(pH8.9)作为运行缓冲液,分离电压1500V,在120s内成功分离检测了两种β-酪啡肽。实验结果表明,β-CM-5和β-CM-7的富集倍数是16倍和21倍,检出限分别是8.2 nmol/L和3.6 nmol/L,线性范围分别是0.05~2μmol/L和0.02~1μmol/L,加标回收率在86.9%~107.5%,该方法可应用于奶制品中β-CM-5和β-CM-7的含量测定。

A rapid and sensitive method was established for the separation and determination of β- casomorphins, including β -CM-5 and 13 -CM-7, by microchip capillary electrophoresis （MCE） coupled with laser induced fluorescence （LIF） detector based on field amplified sample stacking （FASS）. The β- CMs were derivatized with 10 mmol/L boric acid-borate buffer solution （pHS. 7）. The samples were diluted with 5 mmol/L borate buffer solution （pH8.9） and the injection time was 10s. The running buffer was 60 mmol/L borate solution （pHS. 9 ） and the separation voltage was 1500V. β-CM-5 and β -CM-7 were successfully separated and detected within 120s, and enhancement factors of 16-and 21-fold were obtained. The limits of detection were 8.2 nmol/L and 3.6 nmol/L, with spiked recoveries of 86. 9% - 107.5%. The linear ranges were 0. 05 - 2 μmol/L and 0. 02 -1 μmol/L, respectively. The method could be applied to detect β - CM-5 and β - CM-7 in dairy foods, which are significant to the study on biologically active peptides in foods.