MRI as a method for the quantitative analysis of live electroactive biofilms

该项目的总体目标是进一步推进磁共振成像（MRI）作为一种技术，研究电活性生物膜中生物量、化学物质和有效扩散系数的时空分布，特别关注多孔3D电极。在这些条件下的主要挑战将是在导电多孔电极结构中获得足够的灵敏度和分辨率。我们假设通过优化的实验设置和方法可以进一步提高MRI技术的灵敏度。因此，MRI可以作为一种定量和敏感的方法来研究生物质、pH和化学物质（如葡萄糖、乳酸）的分布以及多孔生物膜电极中的有效扩散系数。特别是，我们想要阐明如何通过应用化学交换饱和转移（CEST）来量化pH和在活生物膜/电极结构内积累的相关化学物质来提高分辨率和灵敏度。通过这种方式，MRI可以作为研究复杂生物膜结构内代谢过程和机制的独特工具，使人们能够更深入地了解目前限制此类电极生产力的机制和过程。

Overall aim of this project is the further advancement of magnetic resonance imaging (MRI) as a technique to study the spatial and temporal distribution of biomass, chemical species and effective diffusion coefficients in electroactive biofilms, with a particular focus on porous 3D electrodes. The main challenge under these conditions will be to obtain sufficient sensitivity and resolution inside an electrically conductive porous electrode structure. We hypothesize that by means of an optimized experimental setup and methodology the sensitivity of MRI technology can be further improved. Thus, MRI can be used as a quantitative and sensitive method to study the distribution of biomass, pH and chemical species (e.g. glucose, lactate) as well as effective diffusion coefficients also in porous biofilm electrodes. In particular, we want to elucidate how resolution and sensitivity can be improved by application of chemical exchange saturation transfer (CEST) to quantify pH and relevant chemical species accumulating inside a living biofilm/electrode structure. This way, MRI can serve as a unique tool to study metabolic processes and mechanisms inside complex biofilm structures, enabling a deeper understanding of the mechanisms and processes currently limiting the productivity of such electrodes.