Magnetic-nanoparticles-based fluorescent immunoassay for individual and simultaneous determination of dichlorvos and paraoxon in milk

Abstract

A sensitive and rapid magnetic-nanoparticles-based fluorescent immunoassay (MNPs-FIA) for individual and simultaneous determination of dichlorvos (DDVP) and paraoxon in untreated raw milk was developed. The conjugates DDVP-cBSA (cationized bovine serum albumin) and paraoxon-BSA (bovine serum albumin) were labeled by fluorescent dyes. The optimal amount of immobilized polyclonal anti-DDVP and anti-paraoxon antibodies on MNPs (0.375 mg Ab-MNPs) and optimal concentrations of DDVP-cBSA-FITC (18 µg/mL) and paraoxon-BSA-FITC (22 µg/mL) for MNPs-FIA were determined. The calibration curves of individual and simultaneous immunoassays of DDVP and paraoxon were investigated. The IC 50 value of the individual paraoxon assay in raw cow's milk was 60 ng/mL and linear range 2-300 ng/mL. The IC 50 value of the individual DDVP assay was 70 ng/mL and linear range 5-300 ng/mL. The IC 50 values of the paraoxon and DDVP (100 and 120 ng/mL respectively) in simultaneous assay were higher than those of the individual ones, and their linear ranges were 10-400 ng/mL.

Immunochemical Assays for Determination of Organophosphorus Pesticides in Milk

“…On this principle have been developed assays for the detection of ochratoxin, aflatoxin M1, enterotoxin A, and antibiotics in milk [38][39][40][41]. There are few publications about MNP-based immunoassay for the determination of phosphorus pesticides in milk [42][43][44].…”

Silanized Luminescent Quantum Dots for the Simultaneous Multicolor Lateral Flow Immunoassay of Two Mycotoxins

“…Zearalenone (ZEN) and deoxynivalenol (DON) are produced by Fusarium fungi in maize, barley, wheat, rice, grapes, and other products. Mycotoxins are toxic compounds, and their levels need to be controlled according to food safety regulations. − The multitarget monochrome immunoassays were previously developed with a big variety of labels, such as gold nanoparticles, QDs, carbon, magnetic nanoparticles, and others. − For simplification of visual result evaluation, in present work, we designed and developed a multicolor LFIA with highly intense orange and red fluorescing QDs for fast screening of ZEN and DON.…”