Studies on release of ketorolac tromethamin and indomethacin from ophthalmic hydrogel inserts


KARATAŞ A., Baykara T.

Ankara Universitesi Eczacilik Fakultesi Dergisi, vol.35, no.4, pp.255-268, 2006 (Scopus) identifier

  • Publication Type: Article / Article
  • Volume: 35 Issue: 4
  • Publication Date: 2006
  • Journal Name: Ankara Universitesi Eczacilik Fakultesi Dergisi
  • Journal Indexes: Scopus
  • Page Numbers: pp.255-268
  • Keywords: Hydrogel, Indomethacin, Irradiation, Ketorolac tromethamin, Ophthalmic
  • Ankara University Affiliated: Yes

Abstract

Hydrogels are hydrophilic, three-dimensional networks which are able to imbibe large amounts of water or biolojical fluids, and thus resemble to a large extent biological tissue. The well-tolerated safety and biocompatability of Poly (2 - hydroxyethly methacrylate) and poly (2 -hydroxypropyl methacrylate) hydrogels especially are evident in their use as contact lens and drug release system. In this study, inserts of water-soluble Ketorolac tromethamin (KT) and water- insoluble indomethacin (IND) were prepared using hydrogels such as Poly (butyl methacrylate) (pBMA), Poly (2-hydroxyethyl methacrylate) (pHEMA), and poly (2-hydroxypropyl methacrylate) (pHPMA), and a plasticizer such as Polyethylene glycol 300 (PEG) by film casting method. Swelling properties of these inserts was determined and they were irradiated with an absorbed dose of 1.2 Mrad by means of a Co- 60 source. The effects of these parameters on the drug release were examined. The mechanism of drug release was identified by means of the semi-empirical equation developed by Korsmeyer and Peppas. Swelling of the hydrogels and release of drugs from the hydrogels increased with size of side chain, hydroxyl groups on the side chain of the acrylate and using PEG 300 in the formulation, which increase hydrophilicity. Water-soluble KT showed higher release than water-insoluble IND. It was also observed no effect of irradiation dose on the release of drugs from the inserts. Release of KT mainly fit to the Fickian diffusion mechanism, whereas drug release of IND mainly showed the non-Fickian release mechanism according to their n exponent values.