Study on simultaneous detection of 5 water-soluble vitamins in infant milk powder by HPLC.

This thesis developed a HPLC method for simultaneous determination of 5 Water-soluble Vitamins in infant milk powder.In the method,the analysis column is revered-phase column of Zorbax SB-C8 (5μm,4.6mm×250mm i.d).the mobile phase is Methanol:1g/L CH3 (CH2)6CH2SO3Na (5:95,V/V,pH=3.0) –acetonitrile with gradient elution,the flow is 1.0 mL/min,the column temperature is 25 ℃,and the injection volume is 20 μL.The limit of t quantitation were between 0.5 mg/kg and 5.0 mg/kg,Overall recoveries were between 91.2 and 104.2%,and RSD (n=4)value were between 0.31 and 3.07 %. The results showed that the method was sensitive,accurate,convenient and quick,which can be used to detect simultaneously the 5 water-soluble Vitamins in infant milk powder.