Preparation and evaluation of carvedilol-loaded solid lipid nanoparticles for targeted drug delivery

Purpose: To develop suitable solid lipid nanoparticles (SLN) containing carvedilol (CL) for controlled delivery to site of action. Methods: Solid lipid nanoparticles (SLNs) containing carvedilol (CL) were prepared by hot homogenization and ultrasonication methods. The SLNs were characterized in terms of entrapment efficiency, particle size, zeta potential, polydispersity index, cytotoxicity, solid state characterization and drug release. The stability of the formulations was investigated by monitoring their properties for a period of 3 months. Results: The mean size of the nanoparticles was in the range of 130.70 +/- 1.80 to 154.40 +/- 2.40 nm. Solid state analysis showed that carvedilol was uniformly dispersed in the lipid nanoparticles. Drug entrapment efficiency ranged from 96.03 +/- 0.13 to 93.46 +/- 0.21 % while in vitro cumulative drug release from the nanoparticles in simulated intestinal fluid (SIF) and phosphate buffer containing 30% PEG (pH 6.8) was 96.57 +/- 0.40 and 75.13 +/- 0.15 %, respectively, at the end of 24 h. In vitro release of carvedilol from SLNs followed fist order kinetics and Higuchi diffusion model. Conclusion: The SLNs developed in this study represent a promising safe system for the sustained and controlled delivery of carvedilol.