固相萃取-高效液相色谱法测定饼干中的维生素B12

目的建立固相萃取-高效液相色谱法测定饼干中维生素B12的分析方法。方法样品中的维生素B12用0.1mol/L乙酸钠溶液(pH=4.5)提取,二乙烯苯和N-乙烯基吡咯烷酮共聚物(N-vinylpyrrolidonecopolymer)HLB固相萃取柱净化, 10%的乙腈水溶液定容后用高效液相色谱仪测定。结果维生素B12含量在0.5～10 mg/L线性关系良好,线性相关系数r=0.9999,检出限为0.1 mg/kg。在精密度实验中,相对标准偏差为0.74%～3.75%,在0.3、0.8、1.7mg/kg的添加水平下,加标回收率为93.9%～99.4%。结论该方法准确、高效,适合饼干中维生素B12的测定。

Determination of vitamin B12 in biscuit by solid phase extraction-high performance liquid chromatography

Objective To establish a method for determination of vitamin B12 in biscuit by solid phase extraction-high performance liquid chromatography. Methods Vitamin B12 in the sample was extracted with 0.1 mol/L sodium acetate solution (pH=4.5), purified by divinylbenzene and N-vinylpyrrolidone copolymer HLB solid phase extraction column, and determined by high performance liquid chromatography with a 10% aqueous solution of acetonitrile. Results Vitamin B12 has a good linear relationship at 0.5?10 mg/L, the linear correlation coefficient r was 0.9999, and the limit of detection was 0.1 mg/kg. In the precision experiment, the relative standard deviations were 0.74%?3.75%. The standard recoveries were 93.9%?99.4%, with the spiked concentrations of 0.3, 0.8 and 1.7 mg/kg. Conclusion This method is accurate and efficient, which is suitable for the determination of vitamin B12 in biscuit.