The aim of this research was to investigate the luminescent behavior of ultra-small Eu-activated phosphate and vanadate nanoparticles in the presence of pesticides. Nanoparticles have an average diameter of approximately 2 nm with a narrow size distribution. The monazite crystal structure of phosphate-based particles(space group P121/n1) and single tetragonal zircon-type structure of vanadate-based particles(space group of I41/amd) have been confirmed using X-ray diffraction measurements. All synthesized Eu-activated colloidal nanoparticles show sharp emission peaks in the red spectral region. Photoluminescence measurements revealed emission quenching upon addition of millimolar concentrations of following pesticides: 4-Chloro-2-methyl-phenoxyacetic acid(MCPA), 2,4-Dichlorophenoxyacetic acid(2,4-D) and N-(phosphonomethyl)glycine(Glyphosate). In both phosphate and vanadate-based colloidal nanoparticles luminescence quenching is more evident in the presence of 2,4-D pesticide with the lowest limit of detection(0.7 μM) obtained for phosphate-based nanoparticles.
