In the last decades, a great interest in quantum dots (QDs) has arouse, due to their unique optical properties. High quality QDs can be obtained by high-temperature colloid synthesis in organic solvent. For bioapplication of QDs their surface must be modified with water-soluble biocompatible molecules with maintaining their optical properties. Several approaches including covering with amphiphilic molecules and ligand exchange method (particularly, silanization) have been used for transferring organic QDs to aqueous solution.
Silica-coated QDs possessanomaly high stability, especially in aqueous media.
Silanization enhances QDs bioapplicability, and allows to modify surface charge and functional groups on particle surface. Silanization of CdSe/CdS/ZnS QDs (λem=599 nm) by water-in-oil microemulsion method was carried out. Efficiency of the three various silanization agents (tetraethoxysilane, 3-aminopropyltriethoxysilane and 3-mercaptopropyltrimethoxysilane) for a hydrophilization of QDs was investigated. Obtained water solutions of silanized QDs were stable in time. Quantum yield of initial QDs in toluene and silanized QDs in water as well as ƺ - potential of obtained particles were measured.
Research was supported in the framework of the state task of RF Ministry of Education and Science (project 4.1708.2014K).