Professor Yang
Contact Information
Yang's LaboratoryRoom 532, Lujiaxi Building, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
Ph: +86 (0) 592-218 7601Yanli's work on visual detection of AFB1 toxin accepted by Lab on a Chip. Congratulations to all authors!
Portable Visual Quantitative Detection of Aflatoxin B1Using a Target-Responsive Hydrogel and Distance-Readout Microfluidic Chip
Yanli Ma†, Yu Mao†, Di Huang, Zhe He, Jinmao Yan, Tian Tian, Yuanzhi Shi, Yanling Song, Xingrui Li, Zhi Zhu*, Leiji Zhou and Chaoyong James Yang
Aflatoxin B1 (AFB1), as the secondary metabolite of molds, is the most predominant and toxic mycotoxin that seriously threatens the health of humans and animals. In this work, an AFB1-responsive hydrogel was synthesized for highly sensitive and portable detection of AFB1. The AFB1-responsive hydrogel was prepared using the AFB1 aptamer and its two short complementary DNA strands as cross-linkers. For visual detection of AFB1, the hydrogel is preloaded with gold nanoparticles (AuNPs). Upon introduction of AFB1, the AFB1 aptamer binds with AFB1, leading to the disruption of the hydrogel and release of the AuNPs with a distinct color change of the supernatant from colorless to red. In order to lower the detection limit and extend the method to quantitative analysis, a distance-readout volumetric bar-chart chip (V-chip) was combined with AFB1-responsive hydrogel preloaded with platinum nanoparticles (PtNPs). In the presence of AFB1, the hydrogel collapses and releases PtNPs which can catalyze the decomposition of H2O2 to generate O2. The increasing gas pressure moves a red ink bar in the V-chip and provides a quantitative relationship between the distance and the concentration of AFB1. The method was applied for the detection of AFB1 in beer, with a detection limit of 1.77 nM (0.55 ppb) where an immunoaffinity column (IAC) of AFB1 was used to cleanup and pre-concentrate the sample, which satisfies the testing requirement of 2.0 ppb set by the European Union. The combination of AFB1 responsive hydrogel with distance-based readout V-chip offers a user-friendly POCT device, which has great potential for the rapid, portable, selective, and quantitative detection of AFB1 in real samples to ensure food safety and avoid subsequent economic losses.