Determination of L-lysine Hydrochloride Content in Peibao Capsule by Pre-column Derivation HPLC

OBJECTIVE To establish a method for the determination of L-lysine hydrochloride content in Peibao capsule by pre-column derivation HPLC.METHODS 2,4-DNFB was used as a derivatization reagent and separation of DNP-amino acid derivatives was performed by HPLC with Zorbax SB－C18 column(250 mm×4.6 mm，5 μm). The mobile phase was consisted of acetonitrile and 0.04 mol·L-1KH2PO4 water solution(40∶60). The flow rate was 1.0 mL·min-1with the wavelength at 360 nm. RESULTS L-lysine hydrochloride showed a good linear relationship at a range of 0.12-5.74 μg,r＝0.999 9. The average recovery was 99.55% with RSD=0.48 %(n＝7).CONCLUSION The method is simple, rapid, accurate and reliable, and it can be applied to control the quality of Peibao capsule.