Objective: Present work highlights a strategy to employ solid lipid nanoparticles (SLNs) to encapsulte Atorvastatin calcium (BCS II), which shows low oral bioavailability due to its poor aqueous solubility.
Method: Spherical solid lipid nanoparticles containing atorvastatin calcium were formulated by solvent injection technique and characterized for their size and morphology, entrapment efficiency, stability studies, and drug release dynamics. Factorial design was employed to optimize manufacturing conditions of SLNs using two variables, amount of lipid and amount of surfactant.
Result: Entrapment efficiency of the Atorvastatin calcium loaded SLNs were modeled statistically to attain maximum entrapment efficiency. The drug release behaviour of the optimized formulation F7 was studied in dissolution media and 59% of the atorvastatin calcium from SLN was gradually released during 24 h, which showed efficient sustained release of the drug. In vivo studies on rats indicate oral bioavailability of atorvastatin calcium from spherical SLN was enhanced by 2.74 folds compared to free atorvastatin calcium. After 90 days of storage, >97% ATC remained intact thus the stability of drug was substantially improved by incorporation in to SLN.
Conclusion: These results successfully demonstrate that SLN as a drug delivery vehicle fulfills prolonged release formulation for low bioavailable drugs as well as offers a novel approach to improve oral bioavailability of poorly soluble drugs.