Fluorescence "turn-on" of silicon-containing nanoparticles for the determination of resorcinol.

A fluorescent nanosensor based on silicon-containing nanoparticles (Si CNPs) with green fluorescence (FL) was prepared by one-step method. The prepared Si CNPs emitted green FL at 470 nm under the excitation at 350 nm. The FL signal of Si CNPs reveals an obvious enhancement in the presence of resorcinol (RC), due to the passivation of surface trap states of Si CNPs via the binding of OH group of RC with the NH group of Si CNPs, which allowed the formation of new radiative electron-hole recombination centers. This was confirmed by some analytical experiments performed on zeta potential, FL lifetime steady state, and the FTIR spectra. Most importantly, this nanosensor could selectively determine RC with high sensitivity and without interference from hydroquinone (HQ) and catechol (CT) as RC isomers. RC was detected in the linear range 0.05-40 μM, with a detection limit of 0.012 μM. The synthesized nanosensor was applied to the determination of RC in fresh fruit juice and water samples. The collected results confirmed the feasibility of our approach with high accuracy.