Highly Dispersed 3C Silicon Carbide Nanoparticles with a Polydopamine/Polyglycerol Shell for Versatile Functionalization

defects are attracting considerable attention as next-generation imaging probes and quantum sensors for visualizing and sensing life activities. However, SiC nanoparticles are not currently used in biomedical applications because of the lack of technology for controlling their physicochemical properties. Therefore, in this study, SiC nanoparticles are deaggregated, surface-coated, functionalized, and selectively labeled to biomolecules of interest. A thermaloxidation chemical-etching method is developed for deaggregating and producing a high yield of dispersed metal-contaminant-free SiC nanoparticles. We further demonstrated a polydopamine coating with controllable thickness that can be used as a platform for decorating gold nanoparticles on the surface, enabling photothermal application. We also demonstrated a polyglycerol coating, which gives excellent dispersity to SiC nanoparticles. Furthermore, a single-pot method is developed to produce mono/multifunctional polyglycerol-modified SiC nanoparticles. Using this method, CD44 proteins on cell surfaces are selectively labeled through biotin-mediated immunostaining. The methods developed in this study are fundamental for applying SiC nanoparticles to biomedical applications and should considerably accelerate the development of various SiC nanoparticles to exploit their potential applications in bioimaging and biosensing.

Automated summary

In this study, methods for controlling the physicochemical properties of SiC nanoparticles were developed, including dispersion, surface coating, functionalization, and selective labeling of biomolecules. A thermal oxidation chemical-etching method was successfully developed to deaggregate and produce a high yield of dispersed, metal-contaminant-free SiC nanoparticles. Additionally, controllable thickness polydopamine and excellent dispersity polyglycerol coatings were demonstrated. Furthermore, a single-pot method was developed for selective labeling of CD44 proteins on cell surfaces through biotin-mediated immunostaining. The methods developed in this study are of great importance for the application of SiC nanoparticles in biomedical research and will greatly accelerate their development and potential applications in bioimaging and biosensing.