Preparation of Silicon–Carbon-Based Dots@Dopamine and Its Application in Intracellular Ag⁺ Detection and Cell Imaging

A novel nanocomposite, silicon–carbon-based dots@dopamine (Si-CDs@DA) was prepared using (3-aminopropyl) triethoxysilane, glycerol, and dopamine as raw materials via a rapid microwave-assisted irradiation. This type of Si-CDs@DA exhibited ultrabright fluorescence emission (quantum yield of 12.4%) and could response to Ag⁺ selectively and sensitively. Moreover, the obtained Si-CDs@DA can be further applied in sensing intracellular Ag⁺ and cell imaging, because of its photostability, salt stability, and low cytotoxicity. This study provides a simple and efficient approach for preparing novel Ag⁺ fluorescent probes, which could expand the application of carbon nanomaterials in designing related biosensors.