Preparation of thermoresponsive triclosan poly (N-isopropylacrylamide) nanogels and evaluation of antibacterial efficacy on Cutibacterium acnes

Abstract

The insufficient effects associated with current treatment regimens require the use of novel therapeutic formulations for acne vulgaris. Consequently, this study was undertaken to develop triclosan nanogels of poly(N-isopropylacrylamide) having a thermoresponsive character prepared by surfactant-free emulsion polymerization in the presence of N,N′ methylenebisacrylamide crosslinker. The particle size, zeta potential, thermal analysis, drug loading, swelling capacity, morphological analysis, ex-vivo diffusion, rheological characterization, and the antibacterial potential against causing C. acnes were evaluated. It was observed that the swelling capacity of nanogel formulations increased when triclosan and ethanol were added. All nanogel formulations performed a viscoelastic behaviour at 25 °C and the elastic modulus G′ was higher at 25 °C compared to 37 °C. The results showed that G′ values increased with increasing concentration of hydrophilic monomers. The encapsulation efficiency was obtained as 47.4% and 63.7%. The antibacterial potency of nanogel formulation against C. acnes surpassed the commercial product used as the positive control. According to the study, TCS nanogels of poly(N-isopropylacrylamide) with size and rheological behaviour were found to be suitable for dermal applications. The potent antibacterial activity in thermoresponsive nanogel formulation could be an alternative to existing conventional formulations in the treatment of acne vulgaris.