Objective To investigate the effects of different particle size of Rhizoma Coptidis powder on
pharmacokinetics parameter
of chemical components in rat. Methods HPLC method was applied to determine the concentration of plasma berberine in rat. The plasma concentration- time curve of berberine was dealt with DAS ver1.0software. Then pharmacokinetic characteristics were compared among the normalpowder, ultra-micro powder and nanometer dimension powder. Results the best pharmacokinetics model of berberine in three groups are all one-compartment open model. The main pharmacokinetics parameters of normal powder :Ka=4.15 0.58(1/h),Ke=0.164±0.041(1/h), T1/2ka=0.183±0.035(h), T1/2α=4.52±0.86(h),Tmax=1.63±0.52(h),Cmax=44.05±7.57((g/L),AUC 0～∞ =312.77±118.26((g·h/L);The main pharmacokinetics parameters of ultra-micro powder:Ka=5.23±0.79(1/h),Ke=0.156±0.034(1/h) ,T1/2ka=0.143±0.027(h),T1/2α=4.92±0.88(h),Tmax=1.38±0.52(h),Cmax=62.27±13.73(g/L),AUC 0～∞ =467.94±136.64(g·h/L);The main pharmacokinetics parameters of
nanometer dimensionpowder:Ka=5.82±0.71(1/h),Ke=0.157±0 .026(1/h),T1/2ka=0.123±0.018(h),T1/2α=4.56±0.79(h),Tmax=1.25±0.46(h),Cmax=86.76±19.52(g/L),AUC 0～∞ =567.73±161.78(g·h/L).Compare to the nanometer dimensionpowder, relative bioavailability of normal power and ultra-micro power are 82.42% and 55.13%.Conclusion The absorptive phase of berberine in
Rhizoma Coptidis were improved when they were made into micrometer and nanometerdimension, which can improve the bioavailabilityof berberine clearly.