Autoinducer Sensing Microarrays by Reporter Bacteria Encapsulated in Hybrid Supramolecular-Polysaccharide Hydrogels

Macromol Biosci. 2017 Nov;17(11). doi: 10.1002/mabi.201700176. Epub 2017 Jul 25.


A generally applicable strategy to obtain mechanically robust hydrogels for the incorporation and containment of functional reporter bacteria for the microarray and microparticle-based detection and signaling of N-acyl homoserine lactone autoinducers (3OC12 HSL) at relevant concentrations is reported. For reinforcing hydrogels of 1,4-bi(phenylalanine-diglycol)-benzene (PDB), a hybrid hydrogel is formed by the combination of PDB self-assembly with Ca2+ mediated alginate crosslinking. The different assembly mechanisms are shown not to interfere with each other and despite the more than four-fold increased moduli of the hydrogels, diffusion of autoinducers into the gels remains efficient and Escherichia coli pLuxR-green fluorescent protein (GFP) reporter bacteria are proliferating. Templating affords reporter bacteria-loaded hydrogels with controllable shape and size. Upon exposure to 3OC12 HSL, the embedded bacteria exhibit an up to 12 ± 3 times increase in fluorescence intensity due to autoinducer-triggered GFP expression. This approach can serve as a potentially generally applicable strategy to sensitively detect bacteria via their secreted autoinducers.

Keywords: alginate; bioencapsulation; biosensor; micropatterning; quorum sensing; supramolecular hydrogel.

MeSH terms

  • 4-Butyrolactone / analogs & derivatives*
  • 4-Butyrolactone / pharmacology
  • Alginates / chemistry
  • Escherichia coli / drug effects
  • Escherichia coli / growth & development
  • Escherichia coli / metabolism*
  • Freeze Drying
  • Genes, Reporter*
  • Glucuronic Acid / chemistry
  • Green Fluorescent Proteins / metabolism
  • Hexuronic Acids / chemistry
  • Hydrogels / chemistry*
  • Microarray Analysis*
  • Photoelectron Spectroscopy
  • Polysaccharides / chemistry*
  • Spectroscopy, Fourier Transform Infrared


  • Alginates
  • Hexuronic Acids
  • Hydrogels
  • Polysaccharides
  • homoserine lactone
  • Green Fluorescent Proteins
  • Glucuronic Acid
  • 4-Butyrolactone