C. Sankar

Formulation and biopharmaceutical evaluation of osmotic matrix tablets of diclofenac sodium.

The objective of our study was to prepare and evaluate osmotic matrix (OM) tablets of diclofenac sodium (DS). In vitro studies were done on USPXXIV dissolution apparatus II in different release medium. Surface characteristics of coating films and osmotic contribution of OM tablets also were studied. In vivo evaluation was carried out in 6 healthy human volunteers using HPLC method to assay plasma samples, and the results were compared with the performance of fabricated matrix and two commercial tablets of DS. Through in vitro drug release kinetics, using regression coefficient analysis and Peppas equation, different pharmacokinetic parameters and relative bioavailability were determined. OM tablets were found to provide more prolonged and controlled therapeutic plasma DS levels and also showed improved bioavailability in comparison to fabricated matrix and commercial tablets studied.

Polymer based solutions of bupranolol hydrochloride for intranasal systemic delivery

The present study was aimed at developing intranasal polymer based solutions as alternative route for systemic delivery of Bupranolol hydrochloride (BPH). It is a potent β-blocker drug which upon oral administration undergoes extremely high hepatic first-pass metabolism (>90% in humans). The polymeric solutions were prepared using varying concentrations of polymers like sodium alginate, chitosan, sodium carboxymethylcellulose, methylcellulose (MC), polyvinyl alcohol, carbopol, hydroxypropyl MC, and hydroxypropyl cellulose. The prepared formulations were evaluated in terms of pH of the solution, angular viscosity, drug content, gel strength, gelation temperature, in vitro drug release, in vivo pharmacodynamic studies, histopathological, and stability studies. Except MC based solutions, a biphasic pattern of drug release was obtained in all other cases. Nasal administration of selected batches of polymeric solutions were found to be nontoxic and were able to improve drug bioavailability when compared to oral, nasal, and intravenous solution administrations of BPH.

Oral push-pull osmotic pumps of pentazocine hydrochloride : Development and evaluation

The present study was aimed to formulate and evaluate oral osmotic pumps of pentazocine HCl that are expected to deliver the drug as solution for prolonged period of time with reduced frequency of drug administration and reduced side effects. Push-Pull osmotic pumps of pentazocine HCl were prepared using different formulation variables like diameter of pores, presence of surfactant in formulation core, addition of osmopolymer pectin and presence/absence of water-soluble polymer (carboxymethylcellulose sodium). Fabricated osmotic pumps were evaluated for weight variation, coating thickness, pore diameter, drug content and in vitro release studies. Release rates were found to be independent of size of pores, agitation intensity, and pH of the release medium. The presence of surfactant, water-soluble polymer and osmopolymer (pectin) affected the drug release significantly. Almost all the osmotic pumps gave controlled and prolonged drug release profiles beyond 2 h of lag phase.