Application of chitosan-encapsulated orange oil onto footwear insock leathers spray drying technique for an environmentally sustainable antibacterial formulation

The purpose of this study was to devise an antibacterial treatment for footwear insock leathers. Orange oil-loaded chitosan microparticles were utilised for this purpose. Emulsion formulations with different ratios were prepared, and from these formulations microparticles were manufactured using a spray drying technique. Microparticles obtained in this way were applied to the insock leathers using a finishing process. Successful encapsulation was confirmed by ultraviolet-visible (UV-vis) spectrophotometry, Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM) techniques. The microparticles exhibited highly spheroid shape with a size range of 3–5 µm. Microparticle encapsulation efficiencies ranged from 79.41% ± 3.36% to 86.60% ± 1.13%. After performing microbiological tests and in vitro release studies on the insock leathers, it was determined that the prepared microparticles are able to perform core material delivery. Also, successful microparticle application resulted in these leathers acquiring antibacterial properties. The products and process are biodegradable, nontoxic and biocompatible. © 2020 Johnson Matthey.