Mesoporous silica-coated gold nanorods loaded with tetrazolyl phthalocyanine as NIR light-activated nano-switches for synergistic photothermal and photodynamic inactivation of antibiotic-resistant Escherichia coli

Abstract

A light-controlled nano-switch was prepared by assembling mesoporous silica-coated gold nanorods with bis-(1-(4-hydroxyphenyl)-5-mercapto-tetrazolyl) silicon(IV) phthalocyanines, which exhibited excellent triple functions with controlled release of phthalocyanines and generation of reactive oxygen species (ROS) as well as temperature enhancement under laser irradiation. The nano-switch achieved an effective antimicrobial activity against a variety of antibiotic-resistant Escherichia coli strains through synergistic photodynamic therapy and photothermal therapy by damaging the genomic DNA and enzyme activity of bacteria.