HPLC determination of venlafaxine in human serum and TDM application

Objective To develop an HPLC method for the determination of venlafaxine in human plasma,and analyse the relation between serum clozapine level and its efficacy.Methods A mobile phase was methyl alcohol-water-tetramethylethylenediamine-acetic acid(63∶37∶0.44∶0.37,v/v),an Eclipse DXB-C18 column(150 mm×4.6 mm,5 μm) and UV detector with sensitivity of 0.01 AUFS,with methaqualone as a internal standard.The venlafaxine in the serum was extracted with pentane.The detection wavelength was 230 nm.Results The linear range was from 20 to 1 200 μg·L-1(r=0.999),and the detection limit was 10 ng(S/N=5).The average recovery in the serum was 99.1% and RSD was 1.1% and 4.5% for intra-day and inter-day.The optimal therapeutic concentration was estimated from 130 to 450 ng·mL-1 Conclusion This method is simple,rapid,sensitive,and reproducible.It can be used for clinical drug concentration analysis in the serum.