Development of a Rapid Gold Nanoflowers Immunochromatographic Test Strip Based on the Nanobody for Detection of Aflatoxin B1

Graphical A rapid gold nanoflowers (AuNFs) immunochromatographic test strip (ICTS) based on the nanobody (Nb) was successfully fabricated and used for rapid detection of Aflatoxin B 1 (AFB 1 ). The G8-DIG nanobody was produced via expression and purification which could specifically recognize not only AFB 1 but also DIG-BSA. The proposed ICTS applies nanobody as recognition elements and exhibits excellent performance for detection of AFB 1 for food safety and human health. A rapid gold nanoflowers (AuNFs) immunochromatographic test strip (ICTS) based on the nanobody (Nb) was developed and used for rapid detection of Aflatoxin B 1 (AFB 1 ). Thanks to remarkable physicochemical stability, structural adaptability, ease of genetic manipulation, expression in the prokaryotic system with high yield and tolerance to harsh environments of nanobodies, the G8-DIG was produced via expression and purification, which was labeled with AuNFs by electrostatic adsorption as signal probes in the ICTS. The AuNFs-anti-G8-DIG nanobodies as a probe of ICTS could specifically recognize not only AFB 1 but also DIG-BSA. In this study, the DIG-BSA replaced the anti-6×His-tag antibody of traditional nanobody-based ICTS was coated on the control line, which was easier to synthesize, cheaper, and more stable. Under the optimal conditions, the AuNFs-based nanobody ICTS system accurately detected AFB 1 linearly and dynamically over the range (IC 20 ~IC 80 ) of 1.02~27.86 ng/mL, with the IC 10 and IC 50 of 0.1 ng/mL and 5.46 ng/mL respectively. In addition, these developed nanobodies ICTS had a universal application in the analysis of AFB 1 in corn samples.