高效液相色谱法同时测定乳制品中的泛酸和生物素

目的 建立乳制品中泛酸和生物素的高效液相色谱同时测定方法。方法 样品经硫酸钠沉淀蛋白后，采用C18柱分离，以0.005 mol/L己烷磺酸钠（用磷酸pH值 2.3）:乙腈为流动相，流速为1.0 ml/min，柱温为40℃，检测波长为200 nm。以保留时间定性，峰面积定量。结果 所测2种物质的线性范围为0.10～2.0 μg/ml；相关系数均大于0.999；泛酸检出限为0.082 μg/kg（牛奶）和0.75 μg/kg（奶粉），生物素检出限为0.047 μg/kg（牛奶）和0.43 μg/kg（奶粉）；泛酸测定限为0.27 mg/kg（牛奶）和2.5 mg/kg（奶粉），生物素测定限为0.16 mg/kg（牛奶）和1.4 mg/kg（奶粉）。方法的日内精密度为1.86%～3.79%，日间精密度为2.01%～3.28%。回收率范围为70.9%～106%（奶粉）和72.8%～108%（牛奶）。结论 建立的方法具有简便、快速、重现性好等特点，可用于牛奶和奶粉中泛酸和生物素的同时快速测定。

Simultaneous determination of pantothenic acid and biotin in dairy products by high-performance liquid chromatography

Objective To establish a method for simultaneous determination of pantothenic acid and biotin in milk and milk powder by high-performance liquid chromatography. Methods The protein in sample was precipitated with sodium sulfate and then pantothenic acid and biotin in sample solution were separated with a C18 column under the column temperature of 40℃. The mobile phase was consisting of 0.005 mol/L sodium 1-hexanesulfonate(pH=2.3) and acetonitrile with the flow-rate of 1.0 ml/min. The detection wavelength was 200 nm. The qualitative analysis was based on retention time and the quantification was based on standard curves. Results The linear range of the method was 0.10~2.0 μg/ml and the correlation coefficients ranged from 0.999 to 1.000. The limits of detection(LODs) for pantothenic acid were 0.082 μg/kg (milk) and 0.75 μg/kg (milk powder). The LODs for biotin were 0.047 μg/kg (milk) and 0.43 μg/kg (milk powder). The limits of quantification (LOQs) for pantothenic acid were 0.27 μg/kg (milk) and 2.5 μg/kg (milk powder). The LOQs for biotin were 0.16 μg/kg (milk) and 1.4 μg/kg (milk powder). The intra-day and inter-day RSDs were 1.86%-3.79% and 2.01%-3.28%, respectively. The recoveries ranged from 70.9% to 108%. Conclusion This method is simple, accurate and suitable for the quantification of pantothenic acid and biotin in milk and milk powder.