Integrating Multi-Functionalities Into Non-Spherical Microparticles Fabricated by Top-Down Approach

Inorganic micro- and nanoparticles have promising applications in various domains including nanomedicine. However, those fabricated by top-down approach, which has potential for production of size and shape-specific particles, have not been sufficiently exploited in the domain. In this study, we intend to demonstrate the feasibility of integration of multi-functionalities into one non-spherical microparticle by combining photolithography with self-assembled monolayers. Formation of self-assembled monolayers provides versatile chemical functionalities by tailoring the interfaces between the micro- and nanoparticles of any geometry or size and their environment with molecular precision. Herein, square plate-like gold microparticles were region-selectively functionalized by self-assembled monolayers with two different active terminal moieties such as amine and biotin. Further modification allowed integrating multi-functionalities including fluorescent probes and biomolecules into one particle, which has been confirmed by fluorescence microscopy and scanning electron microscopy. These results suggest a potential use of such non-spherical micro- and nanoparticles with multi-functionalities for target-specific diagnostics and therapeutics.