R Narayana Charyulu

In vitro and in vivo evaluation of chitosan buccal films of ondansetron hydrochloride

Buccal films of ondanstron hydrochloride were fabricated from mucoadhesive polymer, chitosan, and polyvinyl pyrrolidone (PVP K30) for the purpose of prolonging drug release and improving its bioavailability. All fabricated film formulations prepared were smooth and translucent, with good flexibility. The weight and thickness of all the formulations were found to be uniform. Drug content in the films ranged from 98 – 99%, indicating favorable drug loading and uniformity. The inclusion of PVP K30, a hydrophilic polymer, significantly reduced the bioadhesive strength and in vitro mucoadhesion time of the films, although the degree of swelling increased. In vitro drug release studies in simulated saliva showed a prolonged release of over five to six hours for all formulations, except C4, with 99.98% release in 1.5 hours. Kinetic analysis of the release data indicated that the best fit model with the highest correlation coefficient for all formulations was the Peppas model. In vivo studies, on selected films in rabbits, were conducted, to determine the pharmacokinetic parameters such as Cmax, Tmax, and AUC0-∞, using model-independent methods with nonlinear least-squares regression analysis. The AUC and values of Cmax of ondansetron hydrochloride were found to be significantly greater (P < 0.005) than the selected films C2 and C3, as compared to those from the oral solution, thereby confirming improved bioavailability via the buccal route. The Tmax values were also significantly greater (P < 0.005), indicating the slower release of the drug from buccal films, thereby, providing prolonged effects. Good in vitro-in vivo correlation was observed with R2 values exceeding 0.98, when the percentage of drug released was correlated with the percentage of drug absorbed.

Etched ion track polymer membranes for sustained drug delivery

Abstract The method of track etching has been successfully used for the production of polymer membranes with capillary pores. In the present paper, micropore membranes have been prepared by swift heavy ion irradiation of polycarbonate (PC). PC films were irradiated with ions of gold, silicon and oxygen of varying energies and fluence. The ion tracks thus obtained were etched chemically for various time intervals to get pores and these etched films were used as membranes for the drug release. Ciprofloxacine hydrochloride was used as model drug for the release studies. The drug content was estimated spectrophotometrically. Pore size and thus the drug release is dependent on the etching conditions, ions used, their energy and fluence. Sustained drug release has been observed in these membranes. The films can be selected for practical utilization by optimizing the irradiation and etching conditions. These films can be used as transdermal patches after medical treatment.

Nano-lipid Complex of Rutin: Development, Characterisation and In Vivo Investigation of Hepatoprotective, Antioxidant Activity and Bioavailability Study in Rats

The current study was aimed to develop an amphiphilic drug-lipid nano-complex of rutin:egg phosphatidylcholine (EPC) to enhance its poor absorption and bioavailability, and investigated the impact of the complex on hepatoprotective and antioxidant activity. Rutin nano-complexes were prepared by solvent evaporation, salting out and lyophilisation methods and compared for the complex formation. For the selected lyophilisation method, principal solvent DMSO, co-solvent (t-butyl alcohol) and rutin:EPC ratios (1:1, 1:2 and 1:3) were selected after optimisation. The properties of the nano-complexes such as complexation, thermal behaviour, surface morphology, molecular crystallinity, particle size, zeta potential, drug content, solubility, in vitro stability study, in vitro drug release, in vitro and in vivo antioxidant study, in vivo hepatoprotective activity and oral bioavailability/pharmacokinetic studies were investigated. Rutin nano-complexes were developed successfully via the lyophilisation method and found to be in nanometric range. Rutin nano-complexes significantly improved the solubility and in vitro drug release, and kinetic studies confirmed the diffusion-controlled release of the drug from the formulation. The nano-complex showed better antioxidant activity in vitro and exhibited well in vitro stability in different pH media. The in vivo study showed better hepatoprotective activity of the formulation compared to pure rutin at the same dose levels with improved oral bioavailability. Carbon tetrachloride (CCl4)-treated animals (group II) failed to restore the normal levels of serum hepatic marker enzymes and liver antioxidant enzyme compared to the nano-complex-treated animals. The results obtained from solubility, hepatoprotective activity and oral bioavailability studies proved the better efficacy of the nano-complex compared to the pure drug.