Abstract

The effect of molecular weight of poly(vinyl alcohol) (PVA) and sodium chloride on the gelation temperature of methylcellulose (MC) was studied with the objective to develop a MC based formulation for sustained delivery of ketorolac tromethamine a model ophthalmic drug. Pure MC showed sol-gel transition at 61.2 °C. In order to reduce the gelation temperature of MC and to increase the drug release time, PVA was used. Different techniques such as test tube tilting method, UV-vis spectroscopy, viscometry and rheometry were used to measure gelation temperature of all the binary combinations of MC and PVA. It was observed that the gelation temperature of MC was reduced with the addition of 4% PVA and also the extent of reduction of the gelation temperature of MC was dependent on the molecular weight of PVA. The strong interactions between MC and PVA molecules were established using Fourier transform infrared spectroscopy. To study the in vitro drug release properties of the MC-PVA binary combinations, 6% sodium chloride was used to reduce the gelation temperature further up to physiological temperature. It was observed that the drug release time increased from 5 to 8h with the increase of molecular weight of PVA from 9×10(3) to 1.3×10(5) and this was due to the higher viscosity, better gel strength and greater interactions between the drug and PVA molecules in case of PVA (1.3×10(5)) compared to PVA (9×10(3)). In order to have an idea about the nature of interactions between the functional moieties of the drug and the polymer unit of PVA, a theoretical study was carried out.

Links

Publisher Full Text

Authors

Bain MK, Bhowmick B, Maity D, Mondal D, Mollick MM, Paul BK, Bhowmik M, Rana D, Chattopadhyay D

Institution

Department of Polymer Science & Technology, University of Calcutta, 92 A.P.C. Road, Kolkata 700 009, India.

Source

International journal of biological macromolecules 50:3 2012 Apr 1 pg 565-72

MeSH

Drug Carriers
Gels
Ketorolac Tromethamine
Kinetics
Methylcellulose
Models, Molecular
Molecular Conformation
Molecular Weight
Ophthalmic Solutions
Polyvinyl Alcohol
Rheology
Temperature
Viscosity

Pub Type(s)

Journal Article
Research Support, Non-U.S. Gov't

Language

eng

PubMed ID

22301004