Formulation and evaluation of carbamazepine loaded ethosomal nasal in-situ gel for brain targeted drug delivery

This study aimed to develop a novel intranasal drug delivery system for carbamazepine, an antiepileptic drug, to enhance its therapeutic efficacy through targeted and sustained delivery. The goal was to evaluate the suitability of various polymers and excipients for formulating an effective and mucoadhesive nasal gel. Ethosomes were prepared using the cold method and evaluated for particle size, zeta potential, entrapment efficiency, and drug release. Gels were formulated using poloxamer 407 and carbopol 934 and characterized for their physicochemical properties. The optimized ethosomal gel was further assessed for mucoadhesive properties and in vitro drug release. Nasal in-situ gels were also prepared using carbopol and HPMC k 100, and their spreadability and drug release profiles were compared. The optimized ethosomal batch (ET3) exhibited a particle size of 200.7 ​nm, a zeta potential of −54.8 ​mV, and a high drug entrapment efficiency of 93%. The in vitro drug release from ET3 was 88.64%. Among the nasal in-situ gels, the carbopol-based batches demonstrated better spreadability compared to HPMC k 100. The optimized in-situ gel batch (G2) showed a gelation temperature of 33.7 ​°C and an in vitro drug release of 94.05%. The developed ethosomal gel and in-situ gel formulations demonstrated sustained drug release, enhanced mucoadhesion, and targeted delivery, making them promising alternatives for the treatment of epilepsy. This intranasal delivery system could improve patient compliance and therapeutic outcomes by providing a non-invasive and effective route for carbamazepine administration.