Development of a novel niosomal formulation for Gabapentin

Gabapentin is an anticonvulsant drug prescribed to treat partial seizures and neuropathic pain. Nisomes as a type of lipid based drug carriers can improve the pharmacokinetic properties of therapeutic agents. In this study, a niosomal formulation was developed for gabapentin, and then, the cytotoxicity effect of the best niosomal formulation was evaluated on normal cells and colon cancer cell lines.

A number of niosomal formulation were developed and their physicochemical properties were analysed. For G3 and G4 formulations, the release profile complies much better with Korsmeyer- Peppas model and suggesting the Fickian diffusion mechanism in gabapentin release. The effect of the optimized niosomal formulation of gabapentin on the (SW48) colon cancer cell line was assessed by MTT.

The niosomal formulation of G3 showed 60% drug release in 48 hours, and the G4 formulation showed 52%. The cytotoxic effect of optimized formulation (G3) on colon cancer cell line (SW48) resulted in the IC50 of 45µg/ml (200µM) after 48 h, compared to 0.2 mg/mL (1.17 mM) for free gabapentin. As the results confirmed, niosomal formulation of gabapentin is more cytotoxic on colon cancer cell lines compared to pure gabapentin.

The best developed niosomal formulation of gabapentin exhibited good stablity on storage and had a slow and prolonged release of Gabapentin. This niosomal formulation of gabapentin showed cytotoxic effects on colon cancer cells, without significant toxic effect on normal fibroblast cells.