A multifunctional colorimetric sensor array for bacterial identification and real-time bacterial elimination to prevent bacterial contamination

Effective identification and real-time inactivation of pathogenic microorganisms is of great importance for preventing their infection and spread in public health, especially considering the huge threat of coronavirus disease 2019 (COVID-19). Herein, a novel multifunctional colorimetric sensor array with 3,3 ',5,5 '-tetramethylbenzidine (TMB) as a single probe has been constructed. TMB can be efficiently oxidized to generate oxidized TMB (oxTMB) by HAuCl4, which displays four characteristic absorption peaks. The presence of different bacteria could inhibit the oxidation reaction and cause diverse changes in the intensity of the four characteristic peaks. Based on linear discriminant analysis (LDA), not only are nine kinds of pathogenic bacteria successfully identified, but also drug-resistant strains are distinguished from sensitive ones. Interestingly, HAuCl4 can be employed as a germicidal agent to inactivate bacteria during the identification and avoid accessional bacterial contaminations. The developed strategy provides a new and simple avenue for bacterial identification and elimination to effectively protect the public from bacterial contamination.