ß-Cyclodextrin hydrogels for the ocular release of antibacterial thiosemicarbazones.

GLISONI R.J.; GARCIA-FERNANDEZ M.J.; PINO M; GUTKIND G; MOGLIONI A; CONCHEIRO A; ALVAREZ-LORENZO C; SOSNIK A

CARBOHYDRATE POLYMERS

ELSEVIER SCI LTD

Lugar: Amsterdam; Año: 2013 vol. 93 p. 449 - 457

0144-8617

Two types of hydrophilic networks with conjugated beta cyclodextrin (beta-CD) were developed with the aim of engineering useful platforms for the localized release of an antimicrobial  5,6-dimethoxy-1-indanone N4-allyl thiosemicarbazone (TSC) in the eye and its potential application in ophthalmic diseases. Poly(2-hydroxyethyl methacrylate) soft contact lenses (SCLs) displaying pendant beta-CD, namely pHEMA-co-beta-CD, and super-hydrophilic hydrogels (SHHs) of directly cross-linked hydroxypropyl-beta-CD were synthesized and characterized regarding their structure (ATR/FTIR), drug loading capacity, swelling and in vitro release in artificial lacrimal fluid. Incorporation of TSC to the networks was carried out both during polymerization (DP method) and after synthesis (PP method). The first method led to similar drug loads in all the hydrogels, with minor drug loss during the washing steps to remove unreacted monomers, while the second method evidenced the influence of structural parameters on the loading efficiency (proportion of CD units, mesh size, swelling degree). Both systems provided a controlled TSC release for at least two weeks, TSC concentrations (up to 4000ug/g dry hydrogel) being within an optimal therapeutic window for the antimicrobial ocular treatment. Microbiological tests against P. aeruginosa and S. aureus confirmed the ability of TSC-loaded pHEMAco-beta-CD network to inhibit bacterial growth. Keywords: 2-Hydroxyethyl methacrylate; medicated soft contact lenses; superhydrophilic networks; 5,6-dimethoxy-1-indanone N4-allyl thiosemicarbazone; cyclodextrin complexation; antibacterial activity.