Quaternary Ammonium Polyethyleneimine: Antibacterial Activity

Abstract

Quaternary ammonium polyethyleneimine-(QA-PEI-) based nanoparticles were synthesized using two synthetic methods, reductive amination and N-alkylation. According to the first method, QA-PEI nanoparticles were synthesized by cross-linking with glutaraldehyde followed by reductive amination with octanal and further N-methylation with methyl iodide. The second method is based on crosslinking with dialkyl halide followed by N-alkylation with octyl halide and further N-methylation with methyl iodide. QA-PEI nanoparticles completely inhibited bacterial growth (>10 6 bacteria), including both Gram-positive, that is, Staphylococcus aureus at 80 μg/mL, and Gram-negative, that is, Escherichia coli at 320 μg/mL. Activity analysis revealed that the degree of alkylation and N-methylation of the QA-PEI nanoparticles plays a significant role in antibacterial activity of the reagent. The most potent compound was octyl alkylated QA-PEI alkylated at 1 : 1 mole ratio (primary amine of PEI monomer units/alkylating agent). Also, cytotoxicity studies on MAT-LyLu and MBT cell lines were performed with QA-PEI nanoparticles. These findings confirm previous reports that polycations bearing quaternary ammonium moieties inhibit bacterial growth in vitro and have a potential use as additives in medical devices which need antibacterial properties.

Charged hydrophilic polymer brushes and their relevance for understanding marine biofouling

“…Chitosan, a cationic polysaccharide, has antimicrobial activity against both Gram-positive and Gram-negative bacteria (Li et al 2011, Vinsova & Vavrikova 2008. Other cationic polymers containing derivatives of quaternary ammonium amine (Lee et al 2004) and imine (Yudovin-Farber et al 2010), or poly(vinyl-N-hexylpyridinium) (Tiller et al 2001) have also shown antibacterial activity in solution. In comparison to cationic polymers, there are far fewer studies on the effects of anionic polymers on biofouling and these are typically oriented toward biomedical materials (Lei et al 2014, Lord et al 2006).…”

Polyethyleneimine nanoparticles incorporated into resin composite cause cell death and trigger biofilm stress in vivo

“…For this purpose and to overcome the disadvantages of materials that release antibacterial agents (13)(14)(15), we prepared more than 50 derivatives of polycationic particles, starting from different polyamines and alkyl halides that had 4 to 16 methylene groups, using different methods of synthesis. Although some of the tested nanoparticles were found to be effective in inhibiting bacterial growth, octyl alkylated QPEI nanoparticles incorporated into dental resin composite at 1% wt∕wt showed a superior antibacterial effect (16,17). These nanoparticles were mixed into prepolymerized commercially available dental resin composites, modifying the restoration material.…”

Quaternary Ammonium Compounds

“…In a series of publications Weiss and Domb et al . [ 86,87 ] showed that 1 wt% of quaternized cross-linked PEI particles, imbedded in a commercial orthodontic matrix, offered a high killing ef fi ciency. The nonleachability was convincingly demonstrated.…”