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

Coverage of didecyl dimethylammonium bromide (DDAB) on the surface of poly(lactide-co-glycolide) (PLGA) nanoparticles (NPs) was investigated. DDAB-stabilized PLGA NPs (DDAB/PLGA NPs) were prepared by emulsification-diffusion technique with high shear stress. The fabricated DDAB/PLGA NPs were ellipsoidal and positively charged. An increase in the homogenizing stirring rate and in the weight percentage of DDAB in microemulsion reduced the particle size of DDAB/PLGA NPs. When the homogenizing stirring rate increased or the DDAB level in microemulsion decreased, the zeta potential of DDAB/PLGA NPs reduced. In addition, a high homogenizing stirring rate reduced the surface coverage of DDAB on PLGA NPs. The surface coverage of DDAB on PLGA NPs enhanced with increasing the weight percentage of DDAB in microemulsion. The quantity of DDAB attached on the surface could appreciably affect the properties of DDAB/PLGA NPs.