Hollow CoZnSe@CN nanocage with enzymatic activity for determination of tetracycline using smartphone platforms and...

Antibiotic residues in the environment pose a serious threat to ecosystems and human health. Therefore, it is important to develop sensitive and rapid in situ detection methods. In this work, the designed nanozymes, with excellent four enzyme activities, were proved to be constituted of unique hollow nanocage structures (CoZnSe@CN HCs). Based on the peroxidase-like enzymes, a portable colorimetric sensor was constructed for the on-site determination of tetracycline (TC) in real samples. The linear range of TC detection was 0.1-100 μM, and the detection limit was 0.02 μM. At the same time, colorimetric detection and smartphones have also been combined for on-site colorimetric detection of TC. In-depth exploration of the detection mechanism showed that TC could be bound with the material, inhibiting the production of oxidized 3,3',5,5'-tetramethylbenzidine. The sensor was also used for the detection of TC in environmental soil and water samples. This study can provide an intelligent detection method for environmental monitoring.