Pregabalin-loaded transferosomal gel for enhanced topical delivery in peripheral neuropathy: formulation, in vitro and ex vivo evaluation

To formulate and evaluate a pregabalin-loaded transferosomal gel for transdermal delivery aimed at, improving skin penetration, sustaining drug release, and increasing patient compliance in the management of peripheral neuropathy.

Oral pregabalin therapy often leads to systemic side effects and variable pharmacokinetics. A transferosome-based gel offers a novel approach to improve dermal penetration, prolong drug release, and reduce systemic exposure, potentially enhancing therapeutic outcomes in neuropathic pain.

Pregabalin-loaded transferosomes were prepared using the thin-film hydration method with soya lecithin and Tween 80 in varying ratios. Formulations were evaluated for particle size, polydispersity index, zeta potential, entrapment efficiency, and morphology. The optimized formulation was incorporated into a gel and assessed for pH, drug content, in vitro drug release, ex vivo permeation through goat ear skin, irritancy using the hen's egg test on the chorioallantoic membrane, and stability for 90 days.

The vesicles displayed particle sizes of 378.9-1471 nm, a PDI of 0.3-0.8, and a zeta potential from -17.2 to -31.6 mV. Entrapment efficiency[ee] ranged from 40.35% to 89.2%. Scanning electron microscopy confirmed smooth, spherical vesicles. The transferosomal gel showed pH 5.2-6.1 and drug content of 93.4%-98.8%. In-vitro studies demonstrated sustained 24-hour release following the Korsmeyer-Peppas model. Ex-vivo permeation showed 92.2% permeation, a flux of 467.18 µg/cm²/h, and a lag time of 0.99 h. The gel was nonirritant and stable for 90 days.

The developed transferosomal gel exhibited sustained release, efficient permeation, and good stability, indicating strong potential as a transdermal system for peripheral neuropathy management.