Bacterial Biofilm Probed by Scanning Electrochemical Microscopy: A Review

Abstract

Bacterial biofilm, a highly structured community with developmental processes from cell adherence to highly dense biofilms, is of critical concern in many industries. Investigations of parameters mediating biofilm formation, interactions between bacterial species, and parameters governing biofilm stability are quite important for understanding mechanism of biofilm formation. Scanning electrochemical microscopy (SECM), a local electrochemical technique using a microelectrode as its probe, can monitor microbe interactions in situ via detection of small molecules or biochemical cues with spatial and temporal resolution. In this review, we summarize the recent advances in biofilm research using SECM. First, we introduce the applications and potential biochemical cues of biofilms. Then, we classify the applications based on the bacterial species of interest, focusing on SECM to study key biochemical cues and highlighting underlying metabolic processes involved in biofilm formation. Finally, we discuss the challenges and limitations given the complexity and diversity of biofilms for future SECM studies.

How to study biofilms: technological advancements in clinical biofilm research

“…The probe scans the biofilm surface and retrieves information regarding the redox processes around the sample and can provide a micron-scale 3D map of the environment ( Darch and Koley, 2018 ). This methodology can be used to assess the growth and metabolic potential of biofilms (reviewed extensively by ( Zhou et al., 2022 )), but also to measure the antimicrobial effects of electrical stimulation on the biofilm ( Del Pozo et al., 2009 ; Darvishi et al., 2021 ; Darvishi and Girault, 2023 ). SECM can be combined with other microscopic techniques, such as AFM ( Huang et al., 2018 ) and CLSM ( Cannan et al., 2002 ).…”

A Brief Review of In Situ and Operando Electrochemical Analysis of Bacteria by Scanning Probes

“…When image-related information is extracted, SPMs can reveal important physical structures or map specific biomolecules, providing deeper insight into prokaryotes and eukaryotes. Various SPM setups are available for investigating electrochemical systems, including many types such as scanning electrochemical microscopy (SECM), scanning ion-conductance microscopy (SICM), scanning electrochemical cell microscopy (SECCM), and atomic force microscopy (AFM) [6][7][8][9][10][11][12][13][14]. The scanning mechanism of SPMs is based on a probe that is scanned across a sample surface, and the probe-sample interaction is monitored by sensing changes in the local environment.…”

Cytochromecoxidase deficiency detection in human fibroblasts using scanning electrochemical microscopy

“…Biological applications of SECM have been described, including studies of cancer ( 32 – 35 ), cardiac disorders ( 36 , 37 ), oxidative stress ( 38 , 39 ), bacterial metabolism ( 40 – 42 ), and cell interactions in biofilms ( 43 , 44 ). The ability of SECM to detect metabolites locally makes it an ideal tool to discover biomarkers and metabolic redox indicators at the single-cell level ( 39 , 45 , 46 ), which has the potential to enhance the understanding of cellular mechanisms involved in the onset and progression of diseases.…”