Thiolation and PEGylation of silicon carbide nanoparticle

In this study, we implement thiol termination on the surface of few-nanometer-sized silicon carbide (SiC) nanoparticles (NPs) to enable further applications, such as fluorescent biomarkers. Various spectroscopic techniques are employed to monitor the effectiveness of the surface treatment. A thiol-Michael addition reaction is performed by conjugating 4-arm PEGmaleimide molecules to the thiol groups of SiC NPs, further demonstrating the reactivity of thiol-terminated SiC NPs, which also acts as a protection layer against oxidation. These fluorescent thiolated SiC NPs, both with and without conjugated molecules, are directly applicable as bioinert probes. Since SiC NPs can potentially host room-temperature fluorescent defect quantum bits, our results are an important step to realize a bioinert, ultrasmall quantum sensor bioagents, which may open new avenues in biotechnology.