The rapid and reliable evaluation of water quality continues to be an important issue in water safety. Since conventional chemical/physical methods have limitations related to the inability to evaluate the bioavailability of the pollutants or to foresee interactive effects of pollutants in complex water matrices. Therefore, there is considerable interest in developing biological methods to study toxicity and measuring the risk of life-threatening chemicals in the environment. The environment monitoring methodology based on a direct biotoxicity assessment has attracted increasing scientific interests, due to its capability to make the assessment of overall composite toxicity and a promising approach for early risk warning of acute water toxicity. Scientists from the Technical Institute of Physics and Chemistry of the Chinese Academy of Sciences (TIPCCAS) presented the elaboration of a functional organic-inorganic electroactive redox hydrogel (benzoquinone/gelatin/silica hydrogel, BGSH) by combining silica, gelatin and redox mediator benzoquinone (BQ). 3-aminopropyltrimethoxysilane (APTMOS), one of the silane-coupling agents was selected to cross-link gelatin to prepare the gelatin/silica hybrid hydrogel (GSH) and the redox mediator BQ was grafted into the silica backbone by amino group of GSH to prepare benzoquinone/gelatin/silica hydrogel (BGSH). The integrated microbial biosensor was fabricated by immobilizing E.coli within the BGSH on the glassy carbon (GC) electrode. Finally, the integrated microbial biosensor was characterized by CVs, EIS, and also employed to monitor and evaluate the biotoxcity of polluted water of heavy metals. The biotoxicity responses and IC50 results of heavy metals such as Hg2+, Cu2+ and Cd2+ were presented and discussed. Analyst, 2014, DOI: 10.1039/C4AN00243A. |
