Nanostructured Lipid Carrier: A Potential System for Enhanced Oral Bioavailability of Felodipine

Background: Felodipine is BCS class II drug with poor and variable bioavailability due to its insolubility in water (19mg/L) and extensive metabolism in liver and gut. Thus, in the study Nanostructured lipid carriers (NLCs) of Felodipine were formulated to improve its solubility and bioavailability. Methods: NLCs loaded with Felodipine were prepared by high shear homogenization with ultrasonication. The NLCs were characterized for particle size, polydispersity index, entrapment efficiency, content of drug, in vitro drug release studies, stability studies and in vivo bioavailability studies. Results: The mean particle size and polydispersity index for optimized formulation F2 was found to be 187.0±0.06 and 0.259±0.002 respectively. The drug content achieved was between the ranges of 51.15± 0.01 to 69.14±003% for F1 to F5 formulations. The zeta potential of optimized formulation was found to be -38.2 mV, which showed good stability. Formulation F2 showed highest percentage entrapment efficiency of 75.15±0.003. In vitro drug release studies showed sustained release pattern with maximum drug release of 72.82% by F2 formulation at the end of 12h. The bioavailability studies demonstrated significant enhancement in bioavailability of Felodipine NLCs in comparison to marketed product. Stability studies carried out for optimized formulation F2 showed that the NLCs are more stable at 4±2°C. Conclusion: Nanostructured lipid carriers loaded with Felodipine were able enhance the bioavailability of drug by 2.0 folds in comparison to marketed product and also demonstrated sustained drug release pattern for longer period of time.