Mesoporous silica doped with different water-soluble ligands to enhance the antibacterial performance of nano zinc oxides by coordination effect

Abstract

In this work, mesoporous silica was used as an effective nanocarrier to develop a system that coordinated Zn2+ with water-soluble ligands. The obtained nanocomposites showed significant antibacterial properties due to the development of nano zinc oxide. To prepare these nanocomposites, a one-pot method was adopted to synthesize the nano zinc oxide-loaded mesoporous silica (MSN/ZnO) using tetraethyl orthosilicate as a silica precursor, cetyl trimethyl ammonium bromide as a template, zinc acetate as a zinc source, and polyethyleneimine (PEI）or iminodiacetic acid (IDA) as a water-soluble ligand. The physicochemical properties and the morphologies of these nanocomposites were investigated. The results revealed that the particle size of MSN/ZnO decreased effectively with the addition of PEI or IDA. Besides, it was found that the use of water-soluble ligands could improve the loading capacity of mesoporous silica, especially for IDA-MSN/ZnO system, the corresponding zinc element increasing by 114.69%. Due to the increase in the content of nano zinc oxide, these nanocomposites exhibited remarkable antibacterial performance even at a low concentration of 313 ppm. Also, the antibacterial mechanism was elucidated. Therefore, this work provides a facile method for the preparation of antibacterial nanomaterials, and its excellent antibacterial properties make it suitable for practical applications.