An efficient method to improve the dispersion and biocompatibility of ZnO nanoparticles

As an important inorganic antibacterial nanomaterial, zinc oxide nanoparticles (ZnO NPs) have been widely used in biomedical fields. However, the poor dispersion and potential toxicity greatly limit its application. Surface modification is an effective method to improve the dispersion and biocompatibility of ZnO NPs. In this work, ε-polylysine (ε-PL) was grafted on the surface of ZnO NPs via the combination of mussel inspired method and “Michael addition” reaction. The results showed that the ε-PL grafted ZnO (ZnO@ε-PL) could disperse stably in water more than 72 h, demonstrating ε-PL greatly improves the dispersion of ZnO NPs. Furthermore, the cells viability of ZnO@ε-PL at high concentrations (500 μg/mL) was 143.05 ± 12.63%, indicating that the biocompatibility of ZnO@ε-PL is much better than that of ZnO NPs. This study proposed a feasible and effective strategy to improve the dispersion and biocompatibility of ZnO NPs, which may expand the application of ZnO NPs in the biological field.