Integrated circuit-based electrochemical sensor for spatially resolved detection of redox-active metabolites in biofilms

Nat Commun. 2014;5:3256. doi: 10.1038/ncomms4256.

Abstract

Despite advances in monitoring spatiotemporal expression patterns of genes and proteins with fluorescent probes, direct detection of metabolites and small molecules remains challenging. A technique for spatially resolved detection of small molecules would benefit the study of redox-active metabolites that are produced by microbial biofilms and can affect their development. Here we present an integrated circuit-based electrochemical sensing platform featuring an array of working electrodes and parallel potentiostat channels. 'Images' over a 3.25 × 0.9 mm(2) area can be captured with a diffusion-limited spatial resolution of 750 μm. We demonstrate that square wave voltammetry can be used to detect, identify and quantify (for concentrations as low as 2.6 μM) four distinct redox-active metabolites called phenazines. We characterize phenazine production in both wild-type and mutant Pseudomonas aeruginosa PA14 colony biofilms, and find correlations with fluorescent reporter imaging of phenazine biosynthetic gene expression.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Biofilms
  • Diffusion
  • Electrochemical Techniques / instrumentation*
  • Oxidation-Reduction
  • Phenazines / chemistry*
  • Pseudomonas aeruginosa / chemistry
  • Pseudomonas aeruginosa / genetics
  • Pseudomonas aeruginosa / metabolism*

Substances

  • Phenazines