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

Abstract

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 (3OC 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 Ca 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 3OC 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.

Self‐Assembling Supramolecular Hybrid Hydrogel Beads

“…Surprisingly, given the many uses of alginate and the versatility of LMWGs, reports of hybrid gels combining an alginate PG with LMWGs are rare, and in all cases, standard gels were made. [21] To the best of our knowledge, this is the first time a PG has imposed spherical shape onto an LMWG, thus yielding core-shell supramolecular gel beads (Figure 2).…”

Naturally Occurring Exopolysaccharide Nanoparticles: Formation Process and Their Application in Glutathione Detection

“…The high-resolution spectra of elements C, O, and N are depicted in Figure D–F. As can be seen from the high-resolution spectrum of C 1s, peaks at 283.4, 284.8, and 285.9 eV could be assigned to C–(C, H), CC/C–C, and C–N/C–O, respectively. − The O 1s peaks at 530.9 and 531.3 belonged to C–O and CO, respectively. The N 1s peaks at 398.7 and 400.0 eV could be ascribed to C–N–C and NH, giving more evidence that EPS-R503 had amino and amido groups (−CONH−).…”

Evaluation of ligand modified poly (N-Isopropyl acrylamide) hydrogel for etiological diagnosis of corneal infection

“…Although, several systems for the detection of bacteria have been described in the literature and include enzyme-based detection systems ( Shepherd et al, 2011 ; Chen et al, 2015 ; Ebrahimi et al, 2015 ), optimised chemical composition encapsulated in a hydrogel based porous matrix for the detection of Escherichia coli in water ( Gunda et al, 2016 ), hybrid supramolecular-polysaccharide hydrogels ( Li et al, 2017 ), and molecularly imprinted polymers (MIP) systems ( Steen Redeker et al, 2017 ; van Grinsven et al, 2014 ; Betlem et al, 2019 ), so far none of them have been developed for clinical use in man. A review of the field indicates the closest of these systems to offer a single device for rapid detection of microorganisms is a combination of MIPS for binding with an additional disclosure system, such as a thermal sensor ( Betlem et al, 2019 ).…”