A smartphone-integrated method for visual detection of tetracycline

The emergence of “superbugs”, which can cause great panic, has been proved to be related to the pollution of antibiotics in the environment water and food. It is of great research value to develop a portable, on-site and simple method for sensitive and selective detection of antibiotics. In this work, a laponite-based dual-channel fluorescent nanoprobe for the detection of tetracycline (TC) was manufactured through a simple assembly process. The nanoprobe can detect TC within two concentration channel from as low as 30 nM up to 54 μM with a detection limit of 9.5 nM, which met the needs in various analytical samples and showed excellent selectivity over various interferers. More significantly, the paper-based and glove-based visual probes were devised for the detection of TC by multi-color fluorescence change. And the tetracycline was also measured in milk, honey and lake after post-treatment of the samples. Combined with smartphone chromaticity analysis application (APP), the portable and disposable detection of TC can be realized. In addition, according to the fluorescence color change of the probe corresponding to the concentration of TC, two logic gates were also designed, which provided the possibility for the application of the probe in the field of smart devices.