Quarternized Short Polyethylenimine Shows Good Activity against Drug‐Resistant Bacteria

Abstract

The rise in resistant bacteria strains worldwide is proving to be a challenge to the healthcare industry. These “superbugs” are emerging faster than the rate of new antibiotic discovery. This has a heavy impact on medical devices as they are susceptible to biofilm production. Antimicrobial resistance (AMR) causes infections to be difficult to treat, especially postimplantation of a medical device. To prevent bacterial adhesion on devices, various types are coatings are introduced. By binding antibiotics to polymers, an effective adhesive coating on the surface can be created. However, with AMR on the rise, these polymers are losing their efficacy in the application. Another class of antimicrobial polymers with a different mode of mechanism will be explored in this project. Biocidal polymers are effective antimicrobial agents as they rely on the electrostatic interactions between the polymeric charged groups and the charged microbial membrane. Polyethylenimine (PEI) can be modified to achieve a macromolecule containing various charged cationic groups. Quaternizing low‐molecular‐weight PEI with different alkyl groups of short, long, and aromatic groups will give rise to various structural differences. The structure of the quaternized PEI is characterized, and its antimicrobial activity and compatibility are shown to be remarkably improved.

Asymmetric Membrane Capacitive Deionization Using Anion-Exchange Membranes Based on Quaternized Polymer Blends

“… 41 Further signals at 0.8–1.2 ppm match well with literature values assigned to quaternized polyethylenimine after alkylation with a methyl group. 42 Further information on the quaternization of membranes was gathered via elemental analysis ( Table 3 ). The iodide content gives the percentage by mass of counterion within the membrane after methylation.…”

Amphiphilic Polymethyloxazoline–Polyethyleneimine Copolymers: Interaction with Lipid Bilayer and Antibacterial Properties

“…It can be expected that in the typical physiological pH of 7.4, approximately 55% of secondary amine groups are protonated . The usage of C12 side chains allows us to achieve desired hydrophobicity with limited quaternization of nitrogen centers for benefit of higher polymer stability and good solubility in aqueous environment.…”

“…The limited reports available discuss L‐PEI hydrophobic modifications for use as antibacterial surface coatings, typically in the form of covalently bonded polymers or paints . Water soluble (suspendable) L‐PEIs, containing quaternized hydrophobic side chains were investigated as antimicrobial agents in only limited reports …”

Surface Modification of Polyhydroxyalkanoates toward Enhancing Cell Compatibility and Antibacterial Activity

“…Antibiotics‐loaded biomaterials present good activity against broad spectrum microbial, however, antibiotic‐resistant infection is proving to be a challenge to the medical devices, especially for the postimplantation applications. Various synthetic cationic materials and their coatings as the biocidal agents have been developed to selectively target and disintegrate bacterial membranes via electrostatic interacting between the polymeric charged groups and the charged microbial membrane, and inserting into the membrane lipid domains to reduce potential bacterial resistance. Photosensitizers, such as porphyrin‐based antimicrobial materials, utilize the production of singlet oxygen form triplet oxygen generated by photosensitizers toward the elimination of harmful microbial.…”