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Electrically conductive polymers are a groundbreaking class of materials commonly utilized in medical research focused on healthcare devices such as biosensors. They share the mechanical properties of a classical polymer as well as the electronic properties of metals. This allows them to function as flexible, lightweight, and highly efficient components in both wearable and implantable sensor technologies. Although research has shown promising findings, most of the polymer sensors presented are only partially or not at all biologically compatible with the human body. This work demonstrates a new electroconductive polymer matrix composed of bio‐based materials–bovine gelatin, whey protein isolate (WPI), polyaniline (PANI), and phytic acid (PA)– as a soft, compliant material. The results showed a homogeneous and well‐integrated matrix that remains stable up to . The water content in the samples ranged from 29.99% to 63.81%, depending on the method of preparation. The electromechanical properties before and after self‐healing were also investigated, along with antibacterial properties against both Gram‐positive (S. aureus) and Gram‐negative (E. coli) bacteria. This study developed a new formulation of a conductive polymer matrix that is potentially biocompatible, yet still exhibits satisfactory mechanical properties like its predecessors, making it a candidate for bio‐sensing applications.
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Unexpected Enhancement of Antimicrobial Polymer Activity against Staphylococcus aureus in the Presence of Fetal Bovine Serum
Cationic and amphiphilic polymers are known to exert broad-spectrum antibacterial activity by a putative mechanism of membrane disruption. Typically, nonspecific binding to hydrophobic components of the complex biological milieu, such as globular proteins, is considered a deterrent to the successful application of such polymers. To evaluate the extent to which serum deactivates antibacterial polymethacrylates, we compared their minimum inhibitory concentrations in the presence and absence of fetal bovine serum. Surprisingly, we discovered that the addition of fetal bovine serum (FBS) to the assay media in fact enhances the antimicrobial activity of polymers against Gram-positive bacteria S. aureus, whereas the opposite is the case for Gram-negative E. coli. Here, we present these unexpected trends and develop a hypothesis to potentially explain this unusual phenomenon.
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- Award ID(s):
- 1653418
- PAR ID:
- 10314708
- Date Published:
- Journal Name:
- Molecules
- Volume:
- 26
- Issue:
- 15
- ISSN:
- 1420-3049
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.3390/molecules26154512
