Molecular modeling study of antibacterial molecules on nylon 6,6 surfaces

Abstract

Present study is focused on the molecular modeling of various compounds serving as antibacterial agents – nystatin (NYS), chlorhexidine (CH), and dodecyltrimethylammonium bromide (DTAB) – on ideal and imperfect, i.e. containing surface defects, (1 0 0) and (0 1 0) surfaces of nylon 6,6 nanofibers. The study was performed in the Materials Studio/Forcite modeling environment using COMPASS force field. After successful validation of modeling strategy, interactions between the molecule and the surface were monitored. Also the movement of the molecules over the surface was simulated under normal conditions (atmospheric pressure and temperature 25 °C). NYS exhibits the strongest attractive interaction with nylon 6,6 while the weakest interaction was observed in the case of DTAB/nylon 6,6 models. The study revealed importance of size and shape of antibacterial molecules on the interaction. Significantly stronger interaction between DTAB and the imperfect nylon 6,6 surface were observed in comparison with the ideal surface. The diffusion coefficients of single antibacterial molecules were determined on each surface and compared with diffusion coefficients obtained from the models containing higher number of molecules. The results can be used for further experimental research on nonwoven textile prepared from the surface-modified nylon 6,6 nanofibers in various applications where the antibacterial properties are needed.