Conjugated Oligo- and Polymers for Bacterial Sensing

Abstract

Fast and accurate detection of bacteria and differentiation between pathogenic and commensal colonization are important keys in preventing the emergence and spread of bacterial resistance toward antibiotics. As bacteria undergo major lifestyle changes during colonization, bacterial sensing needs to be achieved on different levels. In this review, we describe how conjugated oligo- and polymers are used to detect bacterial colonization. We summarize how oligothiophene derivatives have been tailor-made for detection of biopolymers produced by a wide range of bacteria upon entering the biofilm lifestyle. We further describe how these findings are translated into diagnostic approaches for biofilm-related infections. Collectively, this provides an overview on how synthetic biorecognition elements can be used to produce fast and easy diagnostic tools and new methods for infection control.

Well-defined Conjugated Macromolecules in Sensing

“…Due to the presence Preprints (www.preprints.org) | NOT PEER-REVIEWED | Posted: 9 April 2020 doi:10.20944/preprints202004.0148.v1 of ionic groups, these oligomers are very sensitive to the environment changes, e.g., ionic strength, pH, presence of ions, presence of electrolytes. The charged pendant groups can induce electrostatic interactions with oppositely charged (macro)molecules that reflect in fluorescence properties variation [36]. Moreover, the charges distributed along the oligomer molecules affect their aggregation thus they exhibit high fluorescence response to alterations of aggregates structure and conformational changes.…”

“…For instance, oligo(phenylene ethynylene)s bearing 4-aminophenyl-D-mannopyranoside groups ( Table 1, no. 36,37) in combination with laser scanning confocal microscopy have been used for the detection of E. coli bacteria [79]. Oligomer probes with two mannose groups enable discrimination between uropathogenic and the non-uropathogenic E. coli mutant.…”

“…The current synthesis methods provide access to uniform OArEs of precise length and full sequence control [6,12,35]. OArEs are an important class of sensory materials [26,30,36,37]. OArEs sensors can be used in organic solvents as well as in the aqueous environment or as solid films.…”

Enantiopure polythiophene nanoparticles. Chirality dependence of cellular uptake, intracellular distribution and antimicrobial activity

“…Finally, to verify the possible different behavior of chiral NPs on prokaryotic cells, such as Gram-negative E. coli DH5-Alpha and Gram-positive S. aureus bacteria strain, we have performed different antibacterial tests. 51 A key difference between Gram negative and Gram positive bacteria is the thickness of the cell wall composed by peptidoglycan, in particular Gram positive present a thick layer (20-80 nm) and Gram negative a single layer (1.5-10 nm). In addition, Gram negative present an outer membrane with several pores and appendices.…”

Bacterial Sensing and Biofilm Monitoring for Infection Diagnostics

“…The maintenance of health is a challenge to the healthcare systems, and methods for early diagnostics are essential for the prevention and treatment of diseases. [1][2][3] Detection of bacterial pathogens is important for the treatment of mild-to-life-threatening infections, such as bacterial sepsis, hospital-acquired infections, urinary tract infections, [4,5] sexually transmitted diseases, [6] bacterial foodborne illnesses, [7] etc. Infections are associated or affinity-based interactions with bacterial cells or bacterial biofilms: 1) natural receptors represented by biological components such as toll-like receptors (TLRs), bacteriophages, or antibodies; and 2) synthetic or engineered receptors, such as aptamers, peptides, and cellularly or molecularly imprinted polymers, which are produced to mimic their natural counterpart.…”