Preparation of cefquinome sulfate proliposome and its pharmacokinetics in rabbit.

Cefquinome Sulfate (CS) is a fourth-generation cephalosporin, which has been developed solely for veterinary use. It shows potent antibacterial activity against a broad spectrum of bacterial species. However, Cefquinome is susceptible to hydrolysis, which limiting its clinical employment efficacies to some extent. So, in this study, to increase Cefquinome Sulfate biological half-life, a novel Cefquinome Sulfate proliposome was prepared by solid dispersion and effervescent techniques and characterized for morphology, particle size, entrapment efficiency and in vitro release. A Reversed Phase-High Performance Liquid Chromatography (RP-HPLC) method was first chosen and established to determine the drug concentration in plasma after intra muscular (IM) administrating Cefquinome Sulfate solution and liposome at a single dosage of 18 mg/kg in rabbit. Then their pharmacokinetics in vivo was compared. Results showed that the received liposome was milky white suspension, spherical or ellipsoidal in shape. The mean particle size was 203±5 nm and the entrapment efficiency was 53.5±0.16%. The cefaquinom sulfate solution and liposome both followed a two compartment model, in vivo. The pharmacokinetic parameters for the solution and liposomal formulations were measured as follows: t1/2 α were (1.214 ± 0.135) h and (1.395 ± 0.113) h, t1/2 β were (8.752 ± 0.846) h and (16.503 ± 1.275) h, AUC(0-24) were (49.582 ± 9.173) (mg·h)/L and (138.727 ± 11.034) (mg·h)/L, CL/F were (0.357 ± 0.015) L/(h·kg) and (0.127 ± 0.012) L/(h·kg), MRT(0-24) were (2.68 ± 0.229) h and (5.945 ± 0.479) h, respectively. It could be clearly seen that t1/2 β of liposome prolonged (p < 0.05), AUC and MRT both increased remarkably (p < 0.01), CL/F decreased. Results indicated that this preparation has more residence time and exhibits some sustained-release tendency.