Polydiacetylene (PDA) polymers are increasingly investigated as biosensor. These non-fluorescent and blue chromophores become red and fluorescent when perturbed by certain environmental stimuli such as pH, temperature, metals, biomolecules, and different pathogens. Here, we report the response of stable PDA sensors to Gram-Positive methicillin-resistant Staphylococcus aureus and to small peptide mimics (D-Ala-D-Ala and L-Lys-D-Ala-D-Ala) of their bacterial cell wall. 10,12-pentacosadiyonic acid (PCDA) was covalently modified with antibiotic vancomycin (Van) giving PCDA-Van monomers that could be incorporated within polymers containing variously structured co-monomers. PDA stability was achieved by modification of the co-monomer charge states, effecting surface charge densities. The detection of peptides was dosage dependent and detected by both UV-Vis and fluorescent spectroscopy. The PDA sensors became fluorescent in the presence of S. Aureus bacteria, but showed no significant change in Gram Negative E. coli. A second generation molecule was synthesized with antimicrobial peptides. These PDA polymers also sensed Gram-positive bacteria. The PDA polymer’s size and structure were characterized with dynamic light scattering (DLS) and transmission electron microscopy (TEM) respectively.

Antibiotic-conjugated polydiacetylene (PDA) polymers: synthesis, stability, and gram-positive bacteria detection

Fall 2022 abstracts, posters, and presentations will launch in mid-September.

ACS Fall 2022

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.