Tetraphenylethene-based covalent organic polymers with tunable Electrochemiluminescence for ultrasensitive detection of tetracycline

Tetracycline overuse has become significant threat to human health and ecological security. Therefore, it is urgent to develop an ultrasensitive and highly selective biosensor for fast, trace and precise detection of tetracycline. Herein, we developed an electrochemiluminescence (ECL) biosensing platform for tetracycline detection through using 1,1,2,2-tetrakis(4-(pyridin-4-yl)phenyl)ethene-1,4-bis(bromomethyl)benzene (TPPE-BBMB) covalent organic polymers (COPs). The as-developed ECL biosensor had rapid response, high sensitivity, wide linear range (0.05–20 μM), low limit of detection (2.26 nM), long-term stability and recyclability. The TPPE-BBMB COPs exhibited strong fluorescence (FL) and ECL emission, the maximal ECL efficiency of which was 9-fold higher than Ru(bpy)₃²⁺. The ultrasensitive ECL biosensor has successfully been applied to detect tetracycline in real samples, including milk, lake water and soil samples, which had good recovery rate of more than 93 %. Therefore, the ultrasensitive and highly selective ECL biosensor constructed by TPPE-BBMB COPs will have great potential for trace detection of other such antibiotics.