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

• Preparation of electrophoretic coatings of chitosan–gelatin composites
• Incorporation of ampicillin drug within coatings during the process
• Increased coating degradation with increasing gelatin content
• Highly sustainable and degradation-dependent drug release profiles

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.