Fluorescence quenching of APTES by Fe2O3 nanoparticles – Sensor and antibacterial applications

Abstract

Fe2O3 nanoparticles are particularly attractive for sensor and drug delivery applications because of their size-dependent super paramagnetism, low toxicity, and biocompatibility with cells and tissues. Binding interaction studies of 3-aminopropyltriethoxysilane (APTES) with Fe2O3 nanocrystals have been carried out by absorption, fluorescence, dispersion, SEM, TEM, AFM and FT-IR spectral studies. APTES act as a new host for Fe2O3 nanocrystals that quenches its fluorescence due to the electron transfer of APTES. It adsorbs on the surface of the Fe2O3 nanoparticles. Dispersion studies, SEM and FT-IR confirm the adsorption of APTES on the surface of Fe2O3 nanocrystals. Fe2O3 nanocrystals quench the fluorescence of APTES. Surface treatment of nanoparticles by APTES and its mechanism discussed in detail. Antibacterial test such as well-cut diffusion have been done in agar plates using 100μL concentration of functionalised and non-functionalised Fe2O3 nanoparticles. Functionalised Fe2O3 nanoparticles show enhanced biocidal activity when compared with non-functionalised Fe2O3 nanoparticles in repeated experiments.