The paper aimed at enhancing the antimicrobial activity of chitosan by using tea tree essential oil with the purpose of durably finishing cotton fabrics for use in a hospital environment. The influence of crosslinkers and catalysts on the possibility of obtaining stable bonds using hydrothermal in situ synthesis between cellulosic material and chitosan with and without tea tree essential oil was investigated in detail. The morphology of the sample surface before and after the treatment and textile care cycle was investigated using a field emission scanning electron microscopy (FE-SEM) and indicated the presence of chitosan and a thin film on all treated samples, which showed durability of the treatment. The FTIR spectra obtained by Fourier transform infrared spectroscopy (FTIR) using attenuated total reflection measurement technique (ATR) analysis, showed that all the samples tested recorded physicochemical changes in the structure. The analysis of the samples on the goniometer proved the hydrophilicity of the materials, with a film forming on the surface of the treated samples, which is extremely beneficial given the end use of dressing samples to promote wound healing. The presence of a significant amount of bound chitosan with tea tree oil was confirmed by measuring the mass per unit area of the samples after the treatment and textile care cycles. The results of antimicrobial efficacy show that the materials treated with chitosan were resistant to bacteria and fungi in most cases, but only the samples treated in Bath I showed a zone of inhibition against the fungus Candida albicans, indicating the positive effect of tea tree essential oil.
Keywords: antimicrobial effect; chitosan; cotton; hydrophilicity; in situ hydrothermal synthesis; tea tree oil.