Development of antibacterial textiles by cyclodextrin inclusion complexes of volatile thyme active agents

Abstract

The study aims to develop wash-resistant antibacterial cotton fabrics without using synthetic chemicals. Therefore, natural active agents of thyme, thymol and carvacrol were selected. The inclusion complexes were formed with β-cyclodextrin using kneading method which is a simple and reproducible method for the encapsulation with high production yield. Differential scanning calorimeter analysis showed that 1:1 and 1:2 β-CD: Guest Molecule (M:M) for thymol and carvacrol from different ratios studied has the highest complexation degree as 50% and 100%, respectively. It is also revealed that the volatile agents are retained and showed better thermal stability as a result of complexation. Carvacrol inclusion complexes were found relatively more stable (Zeta potential: −28.2 mV) than thymol complexes with smaller particle sizes (204.9 nm). Chemical structures of the inclusion complexes were revealed with Fourier transform-infrared spectroscopy and nuclear magnetic resonance analyses. The optimum formulations for each active agent were applied to cotton fabrics as per the impregnation method and the capsule treated fabrics were washed 1, 10 and 20 times. The images exhibited the presence of inclusion complexes on the fabrics after 20 washing cycles. Although the antibacterial efficacy of fabrics decreased with increasing washing, the fabrics showed the antibacterial effect after 20 washes against Klebsiella pneumoniae and Staphylococcus aureus. This study showed that the developed products can be an alternative to the other products in the market as the long-lasting fragrant natural antibacterial.