Composite nanoparticles (CNPs) with a core of a noble metal (Au, Ag) and a silica shell serving as a carrier for different target compounds are of considerable interest for solving various applied problems, including the tumor theranostics, the creation of highly sensitive sensors, super-bright emitters (including nanolasers) and different metamaterials. The conventional precursor in the synthesis of such shells is tetraethoxysilane (TEOS), which is characterized by low affinity for the surface of metal cores and poor solubility in water. In addition, as a result of the hydrolytic condensation of TEOS, a dense network of Si–O–Si bonds is formed, which negatively affects the shell capacity for the target compound. All these drawbacks significantly complicate both the obtaining of CNPs and their subsequent loading. In this paper, the possibilities and advantages of alternative approaches to the creation of CNPs based on the replacement of TEOS with functionalized alkoxysilanes are analyzed. The main attention is paid to particles obtained using γ-mercaptopropyltrimethoxysilane.
Kartseva et al. (Wed,) studied this question.