Bioactive wound dressing using bacterial cellulose loaded with papain composite: Morphology, loading/release and antibacterial properties

A bioactive wound dressing consists of a bioactive compound coated on a bio-polymer-based material. In the present study, papain was immobilized on bacterial cellulose (BC) to develop a BC film for dressing application. Pure BC and BC cross-linked with glutaraldehyde (BG) were submersed in papain solution at 25 degrees C and 150 rpm for 24 h. Physicochemical, morphological, loading/release properties and antibacterial activities were determined to analyze the suitability of BC loaded with papain membranes. Scanning electron microscopy/energy-dispersive X-ray spectroscopy and Fourier-transform infrared spectroscopy demonstrated that papain was immobilized successfully on the BC fibrils. The results showed that the presence of glutaraldehyde increased the amount of papain loaded onto the BC, while the releasing property of the BC membranes loaded with papain was active for at least 24 h. The incorporation with papain decreased the crystallinity of the cellulose fiber (from 64% to 55%). This also led to a reduction in the mechanical properties of the wound dressing membranes to half that of the BC. The swelling ratio of BC/papain (BE) and BC/glutaraldehyde/papain (BEG) were at 4546.7 +/- 554.9% and 4296.0 +/- 119.2%, respectively. The results of agar diffusion and cell growth inhibition assay indicated the antibacterial properties of the wound dressing, with tested strains of Escherichia coli (ATCC 25922), Pseudomonas aeuroginosa (ATCC 27853) and Staphylococcus aureus (ATCC 25923) being completely inhibited in the in-vitro test. These findings suggest that the BC dressing produced in this study is a promising material to be applied in the biomedical field.