摘要
目的建立测定婴幼儿配方奶粉中D/L-肉碱含量的高效液相色谱-二极管阵列法和荧光法。方法样品以20%乙醇为提取溶剂,L-丙氨酸-β-萘胺与样品中肉碱反应,反应衍生物通过流动相在C18色谱柱中分离,二极管阵列法采用50 mmol/L p H2.7磷酸二氢钠缓冲液∶乙腈-四氢呋喃（体积比91∶9）为流动相,在紫外波长为244 nm处进行检测。荧光法采用（50 mmol/L p H2.7）磷酸二氢钾缓冲液∶乙腈-四氢呋喃（体积比85∶8∶7）为流动相,在荧光激发波长为280 nm和发射波长为328 nm处,进行检测。结果二极管阵列法中L-肉碱回收率在73%~96%,RSD在3.91%~7.08%;D-肉碱回收率在80%~94%,RSD在4.36%~8.89%。荧光法中L-肉碱回收率在84%~104%,RSD在4.5%~7.0%;D-肉碱回收率在85%~100%,RSD在3.6%~6.2%。结论以上2种方法均适用于婴幼儿配方食品中D/L-肉碱的测定,测定结果差异均无统计学意义（P〉0.05）。但荧光法的检出灵敏度高,更适合婴幼儿配方食品中较低含量的D/L-肉碱检测。
[Objective]To establish the methods for determination of D/L-carnitine in infant formula milk powder by HPLC-DAD and HPLC-FLD.[Methods]Samples were extracted with 20% ethanol and the carnitine in samples was reacted with L-alanine beta naphthylamine. The derivatives of reaction were separated by flow phase in C18 column. For DAD method,the mobile phase was composed of sodium dihydrogen phosphate（50 mmol/L,p H2.7）and acetonitrile-tetrahydrofuran（volume 91∶9）,and the detection UV wavelength was 244 nm. For FLD method,the mobile phase was composed of composed of sodium dihydrogen phosphate（50 mmol/L,p H2.7）and acetonitrile-tetrahydrofuran（volume 85∶8∶7）,while the fluorescence excitation wavelength and emission wavelength was 280 nm and 328 nm respectively. [Results]In the DAD method,the results showed that the recovery rate of L-carnitine was 73%-96%,RSD was3.91%-7.08%,the recovery rate of D-carnitine was 80%-94%,and RSD was 4.36%-8.89%. In the FLD method,the recovery rates of L-carnitine were between 84% and 104%,RSD was 4.5%-7.0%,the recovery rate of D-carnitine was 85%-100%,and RSD was 3.6%-6.2%. [Conclusion]Two methods are both suitable for the determination of D/L-carnitine in infant formula food,and the difference in determination results is not statistically significant（P〉0.05）. FLD method has the higher sensibility,and it is more suitable for the determination of lower levels of D/L-carnitine in infant formula food.
出处
《职业与健康》
CAS
2016年第12期1639-1643,共5页
Occupation and Health
