Univ Rennes, CNRS, Institut des Sciences Chimiques de Rennes - UMR 6226, F-35000 Rennes, France; Instituto de Tecnologia Química e Biológica António Xavier, Universidade NOVA de Lisboa, Av. da República-EAN, 2780-157 Oeiras, Portugal.
Univ Rennes, CNRS, Institut des Sciences Chimiques de Rennes - UMR 6226, F-35000 Rennes, France.
Colloids Surf B Biointerfaces. 2022 Feb;210:112274. doi: 10.1016/j.colsurfb.2021.112274. Epub 2021 Dec 6.
Electrografted anthraquinone on graphite was used as a probe to monitor the pH change at the biofilm-electrode interface at the anode of a microbial fuel cell inoculated with wastewater. The grafting procedure was optimized so that the pH-dependent electrochemical response of the grafted quinone did not overlay with that of the electroactive biofilm. The variation of the formal potential of the grafted quinone as a function of pH was linear over the pH range 1-10 with a slope of - 64 mV. This allowed to monitor the interfacial pH change over three weeks of biofilm colonization of the electrode. During that time the interfacial pH decreased from neutrality to 5.3 while the anolyte only acidified down to pH 6.2. This finding is relevant as local pH change usually leads to alterations of the bioenergetics process of microbial communities and hence on the performance of bioelectrochemical devices.
用电化学接枝法将蒽醌接枝到石墨上，作为探针来监测接种废水的微生物燃料电池阳极的生物膜-电极界面的 pH 值变化。优化接枝过程，使接枝醌的电化学响应与电活性生物膜的电化学响应不会重叠。在 pH 值 1-10 的范围内，接枝醌的形式电势随 pH 值的变化呈线性关系，斜率为-64 mV。这使得可以在电极生物膜定植的三周内监测界面 pH 值的变化。在此期间，界面 pH 值从中性降至 5.3，而阳极电解液仅酸化至 pH 6.2。这一发现很重要，因为局部 pH 值的变化通常会导致微生物群落的生物能量过程发生变化，从而影响生物电化学装置的性能。
