Antimicrobial Activities of Conducting Polymers and Their Composites

Abstract

Conducting polymers, mainly polyaniline (PANI) and polypyrrole (PPY) with positive charges bind to the negatively charged bacterial membrane to interfere with bacterial activities. After this initial electrostatic adherence, the conducting polymers might partially penetrate the bacterial membrane and interact with other intracellular biomolecules. Conducting polymers can form polymer composites with metal, metal oxides, and nanoscale carbon materials as a new class of antimicrobial agents with enhanced antimicrobial properties. The accumulation of elevated oxygen reactive species (ROS) from composites of polymers-metal nanoparticles has harmful effects and induces cell death. Among such ROS, the hydroxyl radical with one unpaired electron in the structure is most effective as it can oxidize any bacterial biomolecules, leading to cell death. Future endeavors should focus on the combination of conducting polymers and their composites with antibiotics, small peptides, and natural molecules with antimicrobial properties. Such arsenals with low cytotoxicity are expected to eradicate the ESKAPE pathogens: Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter spp.

Antimicrobial Activity of Composites-Based on Biopolymers

“…However, this lack of antimicrobial properties can be solved by incorporating or encapsulating antimicrobial agents [60]. Antimicrobial agents must fulfill several requirements, such as a broad antimi-crobial spectrum at a short contact time, ease of preparation at low cost; high stability at the intended applications and storage; and regeneration after the loss of activity [61].…”

Recent Progress of Advanced Metal-Oxide Nanocomposites for Effective and Low-Cost Antimicrobial Activates: A Review

“…Antibiotics are made to prevent the manufacture of bacterial cell walls, proteins, deoxyribonucleic acid (DNA), and other biological processes without being hazardous to nearby tissue to stop bacterial development. Recently, microbial contamination is a significant issue in clinical or hospital settings, medical devices, cleaning supplies, water purification systems, textiles, food packaging, and food storage [1][2][3]. These are brought on by their intricate growth and fast genomic changes for antibiotic adaptation [4].…”

“…One way to address the gaps left by antibiotics is with antimicrobial nanoscale materials [6]. Nanoparticles (NPs) frequently operate at the lowest levels, have a broad antimicrobial spectrum at short contact times, are affordable and easy to prepare, are highly stable in their intended applications and storage, regenerate after losing their efficacy, and enter the ecosystem's food chain directly [3,7]. This antibacterial compound works against fungus, viruses, and protozoa in addition to bacteria.…”

“…3 nanocomposites, the produced material's antibacterial activity was evaluated against the bacterium S. aureus and E. coli. At 60 and 40 μg ml −1 concentrations of Fe 2 O 3 NPs, S. aureus and E. coli exhibit antibacterial action.…”

The Composites of Polyamide 12 and Metal Oxides with High Antimicrobial Activity

“…In the group of metal oxides, titanium dioxide (TiO 2 ) and zinc oxide (ZnO) have been tested as a filler in the polymers to obtain the biocide material. The first one has odor inhibition, a self-cleaning mechanism and low price [ 9 ], while ZnO enhances reactive oxygen species responsible for the bacterial inhibition mechanism [ 10 ]. It has been tested as an effective biocidal material for the protection of old paper documents [ 11 ].…”