Many microorganisms use quorumsensing to regulate several complex phenotypes, and this is accomplished by
the release of a signal molecule(s) into the environment. N-acyl-homoserine lactones (AHLs) are a common class
of signallingmolecule utilized by a range of microorganisms (primarily Gramnegative bacteria but most recently
also archaea) and are often detected through the use of bacterial biosensors. Biosensors can be limited by both
their specificity and sensitivity, and the aimof this studywas to modify and improve current AHL detection strategies.
The biosensoremployed in the present studywas Escherichia coli MT102 harbouring a plasmid containing a
LuxR based biosensor,which produces green fluorescent protein (GFP) as a reportingmechanism. A newmethod
of visualizing the GFP based biosensor overlaid on silica sheets for the purpose of thin-layer chromatography
(TLC) is presented. This new method vastly improves sensitivity of AHL detection by a GFP biosensor than previously
reported and as such represents a powerful new tool in AHL research.