Determination of plasma concentration and bioavailability of mifepristone in dogs by HPLC

Objective To determine the plasma concentration and bioavailability of mifepristone in dogs. Method Samples were extracted and determined by HPLC. The chromatographic conditions included: a Shim pack CLC ODS( 5 μm )reversed phase column( 6 mm × 150 mm ),a MeOH H 2O(78∶22)mobile phase, and UV detection at 302 nm .Results Pharmacokinetic parameters of the test of the mifepristone(1): C max ( 1 399 58± 396 87) ng/mL, T max (2 17±0 98)h, t 1/2( Ke ) (4 32±0 41)h, AUC 0→24 ( 11 043 75± 3111 12 )ng/mL·h, AUC 0→∞ ( 11 318 74 ± 3 099 04 )ng/mL·h.The test of mifepristone(2): C max ( 1 342 60 ± 135 76 )ng/mL, T max (1 33±0 52)h, t 1/2( Ke ) (4 37±0 49)h, AUC 0→24 ( 1 0852 39 ± 1 936 98 )ng/mL·h, AUC 0→∞ ( 11 090 28 ± 1 989 95 )ng/mL·h.The control of Mifepristone: C max (541 80± 152 79)ng/mL , T max (0 92±0 13)h, t 1/2( Ke ) (3 14±0 77)h, AUC 0→24 ( 2 720 28 ± 546 77 )ng/mL·h, AUC 0→∞ ( 2 720 28 ± 546 77 )ng/mL·h.Conclusion It appeared that the two test pharmaceutical preparations and control preparation had marked differences in C max , T max and AUC 0→∞ ( P 0 05).