Surface coverage of didecyl dimethylammonium bromide on poly(lactide-co-glycolide) nanoparticles

► An increase in stirring rate and weight percentage of DDAB reduces the particle size of DDAB/PLGA NPs. ► When the homogenizing stirring rate increases or DDAB level decreases, the zeta potential reduces. ► A high homogenizing stirring rate reduces the surface coverage of DDAB on PLGA NPs. ► The surface coverage of DDAB on PLGA NPs enhances with increasing the weight percentage of DDAB.