Killing two birds with one stone: Construction of a rare earth hybrid dual-channel fluorescent biosensor with intelligent broadcasting function and visualized synchronous assessment of multi-objectives

Contamination of pathogenic bacteria and abuse of antibiotics have become important factors restricting the healthy and rapid development of animal husbandry. Simultaneous quantitative detection of pathogenic bacteria and antibiotics is not only the need of animal husbandry development, but also a challenge in the development of sensor analysis technology. In this study, a dual-channel fluorescent biosensor based on tubular halloysite (THT) loaded with carbon dots and lanthanide bimetal organic frameworks was prepared (THT@CDs-MOF), which contained blue emitters (peak emission at 450 nm under 365 nm excitation) and red emitters (peak emission at 616 nm under 254 nm excitation). The obtained dual-channel biosensor can realize quick visual intelligent assessment of 2,6-pyridinedicarboxylic acid (DPA) through energy transfer under 254 nm excitation and tetracycline (TC) through antenna effect and internal filtering effect (IFE) under 365 nm excitation. This biosensor can detect DPA with a concentration of 0–72 μM (LOD was 6.07 nM) and TC with a concentration of 0–19 μM (LOD was 11.31 nM). By fixing the biosensor on agarose, a biosensor with rapid visualization for simultaneous detection of DPA and TC was obtained. Importantly, a color recognition speech broadcasting system based on 51 single-chip microcomputer for the real-time semi-quantitative identification of DPA and TC was also developed, which promoted the application of artificial intelligence in the field of small molecules analysis.