Transdermal delivery of gatifloxacin carboxymethyl cellulose-based patches: Preparation and characterization

Abstract This study modified carboxymethyl cellulose (CMC) via microwave and prepared gatifloxacin patches through solvent evaporation technique. The prepared patches were investigated with regards to the physical appearance, thickness, weight uniformity, folding endurance, drug content, percent moisture loss, percent moisture uptake, water vapour transmission rate, microbial penetration, skin irritancy, stability, in-vitro drug release, release kinetic, ex-vivo permeation, skin drug retention, and ATR-FTIR of skin. The in-vitro release and ex-vivo permeation experiments were conducted via diffusion cell. It was found that CMC viscosity/molecular weight was reduced as the microwave irradiation time prolonged. All the prepared patches were smooth, clear and elastic and possessed good uniformity in weight, thickness, drug content, % moisture uptake and % moisture loss. The drug content was in the range of 85–95%. The drug release was facilitated by the reduction of CMC viscosity following non-Fickian diffusion mechanism as indicated in kinetic studies. Ex-vivo permeation and skin retention of the drug have been intensified when a low-viscosity polymer was introduced. ATR-FTIR results confirmed that the prepared patches mainly influenced the lipids and proteins of the skin which gave rise to the improved permeation and skin retention of the drug.