Incorporation of the sunscreen agent, octyl methoxycinnamate in a cellulosic fabric grafted with beta-cyclodextrin

The aim of the study was to investigate the incorporation of the sunscreen agent, octyl methoxycinnamate into cyclodextrin cavities covalently bound to cloth fibres. Tencel, a cellulosic fabric, was grafted with β-cyclodextrin molecules through reaction with monochlorotriazinyl-β-cyclodextrin (β-CDMCT). The finished and untreated textiles were soaked in water-methanol mixtures containing 2% (v/v) of sunscreen agent and subsequently subjected to several washing cycles. The unmodified and modified fabrics were characterized by UV spectrophotometry and thermogravimetric analysis. The level of octyl methoxycinnamate entrapped in the Tencel tissue was determined by high-performance liquid chromatography and was found to be much higher (0.0203%, w/w) for the textile functionalised with β-CDMCT compared to the unmodified fabric (0.0025%, w/w). In addition, spectrophotometric assessment of UV transmission through the fabric samples using the Transpore™ test showed that the in vitro sun protection factor of the textile support was markedly enhanced (3.2-fold increase) by impregnation with octyl methoxycinnamate of the β-CDMCT grafted textile. Hence, even after repeated washings, the β-CD finished fabric exhibits higher sunscreen agent retention and photoprotective properties than the unmodified textile material.