Determination of human plasma protein binding rate of nitidine chloride

AIM To develope HPLC for determining the concentration of nitidine chloride in human plasma and to study the plasma protein binding rate of nitidine chloride.METHODS Nitidine chloride was extracted from plasma with ion pair reagent.A mixture of acetonitrile-phosphoric acid(36:64,V:V,pH was adjusted to 3.5 by triethylamine)was used as mobile phase,C_(18) column(250mm×4.6mm,5μm)was selected as the fixed phase.The wavelength of UV detection was 271 nm.Chloramphenicol was taken as an internal standard.Human plasma protein binding rate of nitidine chloride was carried out by equilibrium dialysis. RESULTS Nitidine chloride and the internal standard were separated completely with no interference to other ingredients.The calibration curves of nitidine chloride was in good linear correlation the range of 0.03188- 2.040mg·L~(-1).The low,middle and high three different substantial concentrations with recollection rate95% was demonstrated,and within intra-day and inter-day precisions of low-,mid-,high-concentrations of nitidine chloride in plasma met the requirements of methodology.The plasma protein binding rates of nitidine chloride in low,middle and high concentrations were 68.9%,67.4%,67.9% respectively in human plasma. CONCLUSION The method is simple,fast with sensitive,accurate and reproducible outcomes;satisfing the need for bio-sampling analysis.Nitidine chloride possesses medium capacities of protein binding rate in human plasma,with no significant relation to drug concentrations in dialysis liquid of among low,middle and high concentrations.