Optimal set of electrode potential enhances the toxicity response of biocathode to formaldehyde
Optimal set of electrode potential enhances the toxicity response of biocathode to formaldehyde
复制标题
最佳电极电位组增强生物阴极对甲醛的毒性反应
DOI：
10.1016/j.scitotenv.2018.07.114
复制
发表时间：
2018-12-10
影响因子：
9.8
通讯作者：
Wang, Xin
中科院分区：
文献类型：
--
作者：
Liao, Chengmei;Wu, Jiali;Wang, Xin
自养型生物阴极作为一种广谱、快速、灵敏的传感元件，有望用于水体中有毒物质的早期预警。然而，我们发现，基线电流和响应强烈依赖于阴极电位。在这里，我们将阴极电势保持在0、-0.2和-0.4 V，以研究电极电势对传感器响应度的影响。以甲醛为被测毒物，在-0.2V处的生物阴极具有最高的基线电流（118.2 +/- 10.7 A m（-2））和最低毒性反应浓度（0.00148%），其显示出比普通的（1.4 x 10（4）A%（-1）m（-3））的控制电压，高于0 V（2.3 x 10（3）A%（-1）m（-3））和-0.4 V（2.2 x 10（2）A%（-1）m（-3））下的控制电压。循环伏安法的一阶导数显示，在-0.2 V下驯化的生物阴极具有以0.301 +/- 0.006 V为中心的最高主峰和在-0.2至0.2 V之间的几个次峰。细菌群落分析表明，变形菌和拟杆菌家族与传感性能密切相关。有趣的是，在-0.2V下，NitrospiIidine明显适应，表明属于该门的细菌可能也有助于最高的响应性。结果表明，最佳电极电位对促进生物阴极对甲醛的毒性响应至关重要，差异主要来自于不同电极电位选择的微生物群落。(C)2018爱思唯尔B. V.保留所有权利。
The autotrophic biocathode was promising as a broad spectrum, rapid-responding and sensitive sensing element for the early warning of toxicants in water. However, we found that the baseline current and the responsivity strongly relied on the cathode potential. Here we poised cathode potentials at 0, -0.2 and -0.4 V to investigate the effect of electrode potential on the sensor responsivity. With formaldehyde as the tested toxicant, the biocathode poised at -0.2 V had the highest baseline current (118.2 +/- 10.7 A m(-2)) and the lowest toxicity response concentration (0.00148%), which exhibited a 6-64 times higher response ratio (1.4 x 10(4) A%(-1) m(-3)) than those controlled at 0 V (2.3 x 10(3) A%(-1) m(-3)) and -0.4 V (2.2 x 10(2) A%(-1) m(-3)). First derivative of cyclic voltammetries revealed that the biocathode acclimated at -0.2 V had a highest main peak centered at 0.301 +/- 0.006 V and several minor peaks between -0.2 to 0.2 V. Bacterial community analysis showed that Proteobacteria and Bacteroidetes families closely related to the sensing performance. Interestingly, Nitrospirae was obviously acclimated at -0.2 V, indicating that bacteria belonging to this phylum possibly contributed to the highest responsivity as well. Our findings revealed that the optimal set of electrode potential was critical to promote the toxicity responses of biocathode to the formaldehyde, and the differences were mainly from the microbial communities selected by different cathode potentials. (C) 2018 Elsevier B.V. All rights reserved.