Abstract：A novel long-lasting chemiluminescent (CL) “Three-in-One” Hemin/Fe3O4 @MoS2 hybrid nanozyme powered lab-on-fiber (CN-LOF) device was developed for Ochratoxin A (OTA) detection. The “Three-in-One” nanozymes could catalyze luminol-H2O2 system to produce robust and long-lasting CL under pH range of 6.5–9.0 and temperature range of 0–70 ℃, such excellent catalytic activity was mainly originated from the synergistic effect of MoS2, Fe3O4 and hemin and the nanozyme’s elegant 2D/3D structure. In the reaction system, the nanozymes could continuously catalyze H2O2 to generate O2?? and 1O2 species, which was the main reason for the production of persistent CL. Using OTA antibodies labeled nanozyme for CL signal amplification while a reusable functionalized optical fiber as a biorecognition and separation element and also as a CL transducer, the CN-LOF could quantify OTA with high sensitivity and stability within 20 min. The obtained linear detection range for OTA was 0.69–65.85 ng/mL and the LOD was 0.16 ng/mL under optimal conditions. The proposed CN-LOF method had been successfully applied to the detection of OTA in underground water and milk samples, and the detection results were highly consistent with those of LC-MS, demonstrated the CN-LOF method had great application potential in the analysis of environmental samples and the detection of foodborne biotoxins.

Keywords: Nanozyme; Long-lasting chemiluminescence; Ochratoxin A; Lab-on-fiber; Immunoassay

原文载于:Sensors and Actuators: B. Chemical2023, (SCI, Q1, IF= 8.4).

原文链接：https://doi.org/10.1016/j.snb.2023.134056