Facile synthesis of highly blue fluorescent tyrosine coated molybdenum oxide quantum dots for the detection of imidacloprid pesticide

Abstract

In this work, a facile synthetic route was established for the synthesis of highly blue fluorescent tyrosine coated molybdenum oxide quantum dots (Tyr-MoO3 QDs). Tyrosine (Tyr) was used as a surface ligand for the functionalization of MoO3 QDs with Tyr, thereby generating a highly blue fluorescent Tyr-MoO3 QDs. The obvious color changes were noticed in the solution of MoO3 NPs, MoO3-OH NPs and Tyr-MoO3 QDs under UV lamp and in day light. The Tyr-MoO3 QDs exhibited a maximum emission intensity at 416 nm by applying an excitation wavelength of 330 nm. The as-prepared Tyr-MoO3 QDs acted as a sensor for the fast and sensitive identification of imidacloprid via fluorescence quenching mechanism. The emission peak of Tyr-MoO3 QDs at 416 nm exhibited a linear quenching with increasing concentration of imidacloprid, noticing a good linear relationship between I0/I values and imidacloprid in the range of 0.045–1.00 μM with a correlation coefficient of 0.9955. The developed probe was effectively applied for the detection of imidacloprid in real samples.