Study on the Correlation between Dissolution in Vitro and Absorption in Vivo of Fenofibrate Nanosuspension

OBJECTIVE The dissolution rate in vivo and bioavailability in rats of fenofibrate nanosuspension, coarse and microsize suspension were investigated. The correlations of the drugs in vitro-in vivo were also evaluated. METHODS The drug dissolutions in vitro were measured by UV spectrophotometer, and the plasma concentrations in rats were measured by HPLC. The correlations were studied by the test of dissolution in vitro and bioavailability in vivo through Wagnner-Nelson method. RESULTS The AUC0-36h and C_max of the nanosuspensions were about 10-fold of the coarse and 2-fold of the microsize suspension. The relationship between the dissolution fraction and the absorption fraction was: fa=4.407 9ft-303.31, r=0.983 8. CONCLUSION The dissolution and bioavailability of nanosuspensions enhanced greatly compared with the coarse and microsize suspension. There were good correlationships between dissolution rate in vitro and absorption rate in vivo.