Ophthalmic drug delivery system based on the complex of gellan and ofloxacin

Complex formation between a natural polysaccharide – gellan and an antimicrobial drug ofloxacin was studied in aqueous solution. Conductimetric potentiometric titration curves revealed that forms water-soluble complex of composition 2:1 mol/mol stabilized by ionic hydrogen bonds. The the gellan-ofloxacin confirmed FTIR spectroscopy, dynamic light scattering, zeta-potential thermogravimetric analysis. average hydrodynamic size found 307±5 nm its negative equal to -15 mV. Thin films complex, gelled 0.3 wt.% CaCl2, were used study release kinetics distilled water phosphate buffer. evaluated UV-Vis spectroscopy at λmax = 289 calculated Ritger-Peppas model correspond non-Fickian diffusion Case II transport (zero-order kinetics) cumulative from 96±2% 36±2% buffer water, respectively. It is expected able form situ gel on surface eye prolong residence time tear fluid.