The development of advanced antimicrobial materials has gained significant attention due to the increasing threat of healthcare-associated infections. This study investigates the influence of alkyl chain length in quaternary ammonium compounds (QACs) and fluorine content in fluoro-containing monomers on the surface properties and antibacterial performance of cotton substrates modified via surface-initiated reversible addition-fragmentation chain transfer (RAFT) polymerization. The primary goal was to determine how these molecular parameters synergistically affect surface hydrophobicity, degree of quaternization, microbial adhesion, and antibacterial efficacy.
Quaternized monomers were synthesized by reacting 2-(dimethylamino)ethyl methacrylate (DMAEMA) with either 1-bromooctane (forming DMAEMA + 8) or 1-bromopropane (forming DMAEMA + 3). These were combined with 2,2,2-trifluoroethyl methacrylate (TFEMA) or ethyl methacrylate (EMA) to form copolymer brushes grafted onto cotton fibers. The resulting substrates—designated C8F, C3F, C8NF, and C3NF based on their monomer composition—were systematically characterized using nuclear magnetic resonance (NMR), attenuated total reflectance Fourier-transform infrared spectroscopy (ATR-FTIR), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and contact angle measurements.Phospho-p70 S6 Kinase Antibody Epigenetic Reader Domain
Results demonstrated that the surface degree of quaternization was significantly influenced not only by the alkyl chain length but also by the presence of fluorinated moieties. In particular, substrates grafted with DMAEMA + 8 and TFEMA (C8F series) exhibited a higher degree of quaternization compared to those with shorter chains (C3F series), attributed to enhanced hydrophobic interactions between the longer alkyl chains and fluorinated segments. XPS analysis confirmed a strong correlation between the feed ratio of monomers and the surface atomic percentages of nitrogen and fluorine, indicating successful incorporation of both functional groups.
Contact angle measurements revealed that fluorine content dramatically increased surface hydrophobicity, especially when paired with the shorter C3 alkyl chain.P2RY14 Antibody Cancer However, the hydrophobic nature remained stable over 15 days under ambient conditions, suggesting durability for practical applications.PMID:35263155 SEM imaging showed reduced bacterial adhesion on TFEMA-modified surfaces, particularly against Staphylococcus aureus and Escherichia coli, likely due to both reduced hydrophilicity and electrostatic repulsion from cationic charges.
Antibacterial activity assessments indicated that substrates containing DMAEMA + 8 and TFEMA (C8F) achieved nearly 100% reduction in viable bacteria after 30 minutes of contact, outperforming all other variants. This superior performance was linked to the optimal balance between high surface quaternization, enhanced hydrophobicity, and effective charge distribution. Notably, the antibacterial effect diminished as fluorine content decreased or when non-fluorinated EMA replaced TFEMA, confirming the critical role of fluorination in boosting functionality.
In conclusion, this study demonstrates that combining a longer alkyl chain (C8) with a fluorinated monomer (TFEMA) yields a synergistic enhancement in both surface characteristics and antimicrobial performance. Such tailored design offers a promising strategy for developing durable, multifunctional cotton fabrics suitable for hospital textiles, personal protective equipment, and biomedical devices where resistance to microbial colonization is essential.MedChemExpress (MCE) offers a wide range of high-quality research chemicals and biochemicals (novel life-science reagents, reference compounds and natural compounds) for scientific use. We have professionally experienced and friendly staff to meet your needs. We are a competent and trustworthy partner for your research and scientific projects.Related websites: https://www.medchemexpress.com