Tailoring solubility and drug release from electrophoretic deposited chitosan–gelatin films on titanium

We prepared chitosan–gelatin (Chi–Gel) composite coatings on Ti via electrophoretic deposition (EPD) method for utilization in tissue repair and drug delivery. Uniform coatings were produced over a wide compositional range (0–75% Gel) with coating gains dependent on the EPD parameters including voltage and time. Coating degradation increased as the Gel content increased, with 16–54% weight losses after 3 weeks of immersion in phosphate buffered saline. Ampicillin, used as a model drug, was successfully incorporated within the coatings during the EPD process, and the release was highly sustainable with no burst effect up to a month, proving the potential of these materials as long-term drug eluting coatings. The release rate was dependent on the coating degradation, i.e., the more degradable with increasing Gel content, suggesting a rate-controllable drug release by a compositional change. Preliminary cell tests showed favorable cell adhesion and spreading on the composite coatings, with significant improvement in cell proliferation as Gel content increased. While more in-depth biological assays remain, the Chi–Gel might be useful as a drug eluting electrophoretic coating system on metallic implants for tissue repair.