Deliverable Microparticles Coated With Nano-forest Like Structure To Improve Dispersion and Biofouling Resistance

Abstract Background A variety of implantable microparticles have been developed to detect, diagnose and treat a wide range of diseases, but undesirable bio-fouling caused by biological substances including proteins, bacteria and cells adhesion, can easily lead to the risk of complications such as inflammation. Although most modification techniques have achieved biofouling resistance, the fragility of coatings in fluids and the particles agglomeration often caused by modification limit their applications. Here, we report deliverable microparticles coated with nano-forest like structure (NFMPs) that are exceptionally dispersed and resistant to biofouling. Methods The nano-forest-like microspheres were formed by the combined modification of tree-trunk like nanospikes and dendritic ‘liquid-like’ molecular brush coatings on the conventional microspheres surface. Its structure and surface characteristics were analyzed by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), static contact angles (CAs), slide angles (SAs). Compared the dispersibility of nanospike-modified hydrophobic microspheres with conventional hydrophobic microspheres in water to determine nanospike-induced abnormal dispersion. Furthermore, the nano-forest-like microparticles were incubated with proteins, bacteria and cells to verify their anti-biofouling properties, and its anti-adhesion mechanisms were explored through activity tests and anti-biofouling performance tests of nanoforest structure-modified planar structures. Results The ‘liquid-like’ coating is reliably biocompatible and induces microparticles to exhibit long-term and robust resistance against proteins, bacterial and cells adhesion. While the microparticles were aggregated in water due to their increased hydrophobicity caused by the coating, the tree-trunk-like nanospikes induced specific dispersion of the microparticles. Conclusion Based on these results, our research introduces a unique modification technology for deliverable microparticles with exceptional dispersibility and anti-biofouling properties, which will facilitate the development of deliverable devices or materials to reduce inflammation or infection.