title: Biodegradable hybrid polymeric membranes for ocular drug delivery.
abstract: Ophthalmic delivery systems such as ocular inserts are useful strategies to improve the ocular bioavailability of topically administered drugs. In the present study polyvinyl alcohol and sodium carboxymethylcellulose based ocular inserts were prepared by solution casting for sustained drug delivery of ciprofloxacin for treatment of topical infections. The polymers were esterified and the formation of ester bonds was confirmed by Fourier transform infrared spectroscopy. The inserts had a smooth structure with a surface roughness of 7.3 nm. Inserts were found to be wettable by simulated tear fluid with contact angle <45 degrees . Mechanical testing results indicated that the tensile strength of polyvinyl alcohol-sodium carboxymethylcellulose (10:2 wt.%) inserts was up to 8.9 + or - 1.9 MPa, which is adequate to resist the pressure likely to be exerted during application. In vitro drug release kinetics showed sustained release of ciprofloxacin for up to 48 h from the inserts. Sodium fluorescein-loaded inserts showed higher penetration of the dye in the posterior segment tissues of explanted goat eye balls as compared with an eye drop solution of sodium fluorescein. The inserts were non-toxic to corneal epithelial cells and showed no signs of acute ocular toxicity in in vivo studies in albino rabbits.
authors.affiliation: Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Mumbai 76, India.
authors.forename: Dharmendra
authors.initials: D
authors.lastname: Jain
authors.forename: Edmund
authors.initials: E
authors.lastname: Carvalho
authors.forename: R
authors.initials: R
authors.lastname: Banerjee
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001672:Biocompatible Materials / Q000494:pharmacology*; D002266:Carboxymethylcellulose Sodium / Q000737:chemistry / Q000494:pharmacology*; D002460:Cell Line; D002939:Ciprofloxacin / Q000494:pharmacology; D016503:Drug Delivery Systems / Q000379:methods*; D004926:Escherichia coli / Q000187:drug effects; D005123:Eye / Q000187:drug effects*; D006041:Goats; D006461:Hemolysis / Q000187:drug effects; D006801:Humans; D055595:Mechanical Phenomena / Q000187:drug effects; D008567:Membranes, Artificial; D008826:Microbial Sensitivity Tests; D018625:Microscopy, Atomic Force; D008855:Microscopy, Electron, Scanning; D009077:Mucins / Q000378:metabolism; D011142:Polyvinyl Alcohol / Q000737:chemistry / Q000494:pharmacology*; D017550:Spectroscopy, Fourier Transform Infrared; D013211:Staphylococcus aureus / Q000187:drug effects; D023382:Toxicity Tests, Acute; D017155:Wettability / Q000187:drug effects
chemical_list: D000900:Anti-Bacterial Agents; D001672:Biocompatible Materials; D008567:Membranes, Artificial; D009077:Mucins; D002939:Ciprofloxacin; D011142:Polyvinyl Alcohol; D002266:Carboxymethylcellulose Sodium