Ultrasensitive immuno-PCR for detecting aflatoxin B₁ based on magnetic separation and barcode DNA

It was desired to develop the ultrasensitive and efficient strategy for detecting ultratrace aflatoxin B₁ (AFB₁) and protecting consumers' health. In this study, a magnetic immuno-PCR method (MIPCR) based on the barcode DNA was described and evaluated for detecting AFB₁ in agricultural by-product samples. Under the optimal MIPCR, the limit of detection (LOD) was 0.01 pg mL⁻¹, the half inhibitive concentration (IC₅₀) was 1.72 pg mL⁻¹, and the detection range was between 0.01 and 100 pg mL⁻¹. The LOD and IC₅₀ showed 480-fold and 21-fold lower than that of ELISA, respectively. The sensitivity of MIPCR had reached an ultratrace level and considerably improved. The reasonable specificity, precision and accuracy had been demonstrated. Furthermore, the high reliability and applicability of the MIPCR had been further confirmed by the good correlation of LC-MS/MS for the authentic samples. The proposed MIPCR had significantly shortened the analytical procedure, testing time and workload through the powerful probes and magnetic separation, which indicated the high-efficiency performance. This study could provide an alternative approach to detect the AFB₁ contamination, and a critical reference for the ultrasensitive and efficient detection of other hazardous chemicals.