Search

This study presents a method of producing biocompatible nanofibrous composites containing antimicrobial polymers which have excellent antimicrobial efficacy. Specifically, antimicrobial cellulose acetate (CA) nanofibrous composites were prepared by adding poly[5,5-dimethyl-3-(3′-triethoxysilylpropyl)hydantoin] (PBA) to the CA solution using the electro-spinning technique followed with curing and exposure to diluted sodium hypochlorite. Scanning electron microscopy images demonstrated that CA nanofibers formed with diameters of 172 ± 62 nm. The chlorinated CA nanofibrous mats showed good UVA stability. The chlorinated CA nanofibrous mats completely inactivated Staphylococcus aureus (gram-positive) and Escherichia coli O157:H7 (gram-negative) within 30 min of contact time. The cell culture assay showed that the N-halamine-modified CA nanofibrous composites are non-toxic in vitro. [ABSTRACT FROM AUTHOR]

Two N-halamine precursors, 1-glycidyl-s-triazine-2,4,6-trione and 1-(2,3-dihydroxypropyl)-s-triazine-2,4,6-trione, were synthesized and tethered onto cotton fabrics via the crosslinking agent 1,2,3,4-butanetetracarboxylic acid. The modified samples were characterized by Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscope (SEM). The modified fabrics were rendered biocidal activities upon exposure to dilute hypochlorite solutions. The chlorinated cotton swatches were challenged with Staphylococcus aureus (ATCC 6538) and Escherichia coli O157:H7 (ATCC 43895) and exhibited excellent biocidal efficacy. The stability and rechargeability of the modified samples during washing and ultraviolet irradiation were also investigated. In vitro cell cytocompatibility studies demonstrated that the antibacterial cotton has good biocompatibility. [ABSTRACT FROM AUTHOR]

ABSTRACT This study reports the formation of cyanuric chloride hydrolysate and its attachment onto cellulose fibers though covalent bonding. The hydrolysis product, 2,4-dichloro-6-hydroxy-1,3,5-triazine, is prepared in water solution at ambient temperature, and directly used as a treatment solution for the treatment of cotton fabrics without any prior work-up. The triazine treated fabrics are rendered antimicrobial through exposure to chlorine bleach. The oxidative chlorine bonded to the triazine-treated cotton is very stable and regenerable to standard washing tests and UVA irradiation test. The N-halamine modified cotton fabrics demonstrate excellent antimicrobial efficacy against Staphylococcus aureus ATCC 6538 and Escherichia coli O157:H7 ATCC 43895 with 7-logs reductions within the contact time of 10 and 5 min, respectively. In addition, the results of in vitro cell viability test suggested that the N-halamine modified fabrics have excellent cytocompatibility to mammalian cells. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40627. [ABSTRACT FROM AUTHOR]

Quaternary ammonium salts and N-halamines are widely used as biocides in antimicrobial coatings, and have been extensively studied over the past two decades. In this work, 5,5-dimethyl-3-(3′-triethoxysilylpropyl)hydantoin (SPH), and 3-(trimethoxysilylpropyl) octadecyl dimethyl ammonium chloride (SPODA) were synthesized and coated onto cotton fibers using a pad-dry process (PD) and the traditional pad-dry-cure process (PDC). The coated cotton swatches were characterized by FT-IR and SEM. The quaternary ammonium salt showed a relatively lower inactivating bacteria efficacy than did the N-halamine compounds. The chlorinated swatches coated with both SPH and SPODA using the PD process could inactivate about 7 logs of the Staphylococci aureus within 5–10 min and 7 logs of Escherichia coli O157:H7 within 10–30 min, respectively. The addition of quats in N-halamine coatings improved antimicrobial activity against Gram-negative bacteria E. coli O157:H7. However, this result was not observed when the PDC process was applied in coatings because of the increasing hydrophobicity of the coated samples under high coating temperature. [ABSTRACT FROM AUTHOR]

A novel N-halamine precursor with tertiary amino group (5,5-dimethylhydantoinyl-3-ylethyl)-dimethylamine (DEADH), was synthesized and then covalently bonded onto cotton fabrics modified by 3-chloropropyltrimethoxysilane to form quaternarized N-halamine precursor grafted cotton fabrics which could be transferred to N-halamine structure upon exposure to dilute sodium hypochlorite solution. The grafted cotton fabrics were characterized by FT-IR, X-ray photoelectron spectroscopy, and field emission scanning electron microscope. The antimicrobial test showed that the cotton fabrics grafted with the quaternarized N-halamine were capable of 7-log inactivation of Staphylococcus aureus and Escherichia coli O157:H7 within 1 min of contact time. Very interestingly, it was found that the grafting process and following chlorination had almost no adverse effect on the tensile strength of cotton fabrics. Furthermore, the antimicrobial cotton fabrics exhibited good washing durability and stability. [ABSTRACT FROM AUTHOR]