Preparation of novel biodegradable ropivacaine microspheres and evaluation of their efficacy in sciatic nerve block in mice

摘要: In this study, ropivacaine chitosan-loaded microspheres for subcutaneous administration were developed. The systems characterized in terms of surface morphology, particle size, encapsulation efficiency, and vitro release behavior. Results showed that the had drug loading rate 7.3% efficiency 91.2%, their average diameter was 2.62±0.76 µm. morphology study revealed are uniform monodispersed spheres did not form aggregates aqueous solution. It clearly observed profile exhibited a biphasic pattern: initial burst within first 2 hours following slower sustained over long time. vivo, greater area under plasma concentration-time curve from 0 to t (AUC0- ) obtained (4.27-fold), than injection group, which indicated there significantly improved systemic exposure ropivacaine. Pharmacodynamics result preparing as microsphere preparation could only extend effect time but also decrease dosage.