Controlled release of clove oil from chitosan/gum Arabic microcapsules: insights from microstructure and application in multifunctional fabrics

Recently, there has been a growing consumer demand for mosquito-repellent textile materials as a preventive measure against mosquito-borne diseases, such as malaria and dengue. Although these textiles initially exhibit strong repellency, their effectiveness significantly diminishes after repeated washing cycles. In this study, were development of multifunctional fabrics, where the clove essential oil (CEO) encapsulated-chitosan/gum Arabic has been prepared using the complex coacervation and functionalization on textile structures, using the padding method. Moreover, different 100% fiber fabrics (cotton, polyamide, and polyester), two surfactants (Tween® 20 and SPAN® 80), and different molecular weights of chitosan (Ch) were studied for comparison on the microcapsule’s encapsulation properties. A commercially citric acid binder was used for the chemical functionalization of the microcapsules on the textile substrate. The average distribution of microcapsules was studied, and the finished fabrics were characterized for surface morphology, physical–chemical functionalities, thermal properties, conventional textile properties, including release profiles, and finish washing cycle test, investigated by whiteness and color parameters tests conducted according to international standards. The results obtained show a successful CEO-encapsulation reaching a 75.83% maximum of CEO-loaded, and the color properties do not show a significant interference among samples, using a citric acid binder on fabrics functionalization, reaching a 114.27 CIE WI maximum for Cotton fabric, due to the standard detergent used in the wash test. The experimental results of the final EO-release demonstrate the reservoir effect of the CEO, with the low Ch and SPAN® 80 surfactant being more stable to EO-release, especially in polyamide fabric with ∼2250 mg/L before and ∼175 mg/L after the wash test was performed, respectively. The results of the functionalized fabrics demonstrated long-lasting performance from CEO microcapsules, even after undergoing washing cycle tests.