Abstract:Based on upconversion fluorescence labeling, magnetic separation and immunological recognition, a novel detection method of Vibrio parahaemolyticus was constructed. Primarily, the NaY0.78F4: Yb0.20, Er0.02 upconversion nanoparticles(UCNPs) were synthesized through hydrothermal method, and then amino group was modified on the surface of UCNPs. Meanwhile, amino-modified MNPs were synthesized by one-step process. Secondly, the antibodies of Vibrio parahaemolyticus binding with MNPs and antibodies of flagellin binding with UCNPs were used as capture probes and signal probes, respectively. The composite of MNPs-target bacteria-UCNPs was obtain, and detected by 980 nm laser. Under the optimum conditions, the upconversion fluorescence was a good linear in the range of 5×103~5×105 cfu/mL of Vibrio parahaemolyticus, and the detection of limit was 1×103 cfu/mL. This method was accurate in the recovery text in the crucian.