A novel biocidal styrenetriazinedione polymer

Antibacterial N-halamine fibrous materials

Pathogenic microbial contamination poses serious threats to human healthcare and economies worldwide, which instigates the booming development of challenging antibacterial materials. N-halamine fibrous materials (NFMs), as an important part of antibacterial materials, featuring structural continuity, good pore connectivity, rapid sterilization, rechargeable bactericidal activity, and safety to humans and environment, have received significant research attention. This review aims to present a systematic discussion of the recent advances in N-halamine antibacterial fibrous materials. We firstly introduce the chemical structures and properties of N-halamine materials. Subsequently, the developed NFMs can be categorized based on their fabrication strategies, including surface modification and one-step spinning. Then some representative applications of these fibrous materials are highlighted. Finally, challenges and future research directions of the materials are discussed in the hope of giving suggestions for the following studies.

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The chemical structures and properties of N-halamine materials are briefly introduced.

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Design and fabrication strategies of N-halamine fibrous materials are systematically reviewed.

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The functional applications of the N-halamine fibrous materials are discussed.

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Challenges and future research directions of the antibacterial N-halamine fibrous materials are provided.

Preparation, Post-Modification, and Antibacterial Application of Gelatin Electrospun Membranes

Two bis(diaryldiazomethane)s substituted with amino groups are synthesized and used for the surface modification of membranes electrospun from gelatin. These membranes are then reacted with tolylene-2,4-diisocyanate to give urea-functionalized materials, so that hydrogen peroxide can be reversibly bound onto their surface. These membranes are characterized by scanning electron microscopy, XPS, differential scanning calorimeter, and tensile test to show their surface properties and bulk properties. The surface modification with amino-substituted diazomethanes and the subsequent cross-linking reaction with diisocyanates contribute to high loadings of hydrogen peroxide, and greatly increase the antibacterial activity of gelatin-derived membranes, which open a new horizon in the preparation of high loading antiseptic/antibacterial biomacromolecular surfaces and interfaces.

Effective surface attachment of Ag nanoparticles on fibers using glycidyltrimethylammonium chloride and improvement of antimicrobial properties

Functional m-aramid fibers with antimicrobial properties by reaction of glycidyltrimethylammonium chloride with silver nanoparticles.

Biocidal Copolymers of N-Haloacryloxymnethylhydantoin

A series of new biocidal copolymers containing N-chloro-and N-bromo-acrYloxymethylhydantoin moieties have been prepared in granular form, as surface coatings and as grafts to fibers. The copolymers have been tested for bactericidal effects against Staphylococcus aureus and have been evaluated for stability in terms of retention of their biocidal halogen contents. They have been demonstrated to have potential application for polymeric materials for which a biocidal functionality might be benefical.

New N-Halamine Biocidal Polymers

A new series of N-halamine polymers has been synthesized and tested in granular form, on glass and as fiber substrates for efficacy at inactivating bacteria. Copolymers and grafted copolymers were prepared with 4-(alkyl acryloxymethyl)-4-ethyl-2-oxazolidinones and commercial monomers or polymers. These polymers are inexpensive to synthesize and are efficient biocides in granular form and as surface-coated disinfectants. They can be coated on glass, plastic, and fibrous materials, which gives them considerable potential as commercial disinfectants. They could be used for a variety of industrial, commercial, and medical applications.

Functionalization of Polystyrene with Cyclic Anhydrides and their Spectroscopic, Adhesive and Corrosive Characterizations

Polystyrene (PS) has been chemically modified with cyclic anhydrides such as glutaric anhydride (GA), citraconic anhydride (CA) and phthalic anhydride (PA) in the presence of BF3·O(C2H5)2 in chloroform and succinic anhydride (SA) in 1,2-dichloroethane. Some important reaction parameters were determined in order to optimize the acylation process. ATR FT-IR and 1H NMR studies indicate that the acylation reaction can introduce both carboxyl group and double bond (for only citraconic anhydride) onto pendant aromatic groups of the polymer. The adhesion properties and corrosion resistance of the acylated PS on metal surface under various conditions have been investigated.

Light and dark-activated biocidal activity of conjugated polyelectrolytes

This Spotlight on Applications provides an overview of a research program that has focused on the development and mechanistic study of cationic conjugated polyelectrolytes (CPEs) that function as light- and dark-active biocidal agents. Investigation has centered on poly-(phenylene ethynylene) (PPE) type conjugated polymers that are functionalized with cationic quaternary ammonium solubilizing groups. These polymers are found to interact strongly with Gram-positive and Gram-negative bacteria, and upon illumination with near-UV and visible light act to rapidly kill the bacteria. Mechanistic studies suggest that the cationic PPE-type polymers efficiently sensitize singlet oxygen ((1)O(2)), and this cytotoxic agent is responsible for initiating the sequence of events that lead to light-activated bacterial killing. Specific CPEs also exhibit dark-active antimicrobial activity, and this is believed to arise due to interactions between the cationic/lipophilic polymers and the negatively charged outer membrane characteristic of Gram-negative bacteria. Specific results are shown where a cationic CPE with a degree of polymerization of 49 exhibits pronounced light-activated killing of E. coli when present in the cell suspension at a concentration of 1 μg mL(-1).

New approach to produce water free of bacteria, viruses, and halogens in a recyclable system

The antimicrobial activity of a new cross-linked N-halamine polymer against bacteria and viruses was evaluated. The polymer achieved a 9-log(10) reduction of bacteria (both Escherichia coli and Staphylococcus aureus) in 1.5 h and a 5-log(10) reduction of bacteriophage PRD1 in 3 h. At the same time, the ability of the nonhalogenated polymer to trap halide ions was examined. The polymer was incorporated into a multifiltration system to study the ability to produce water free of bacteria, viruses, and halide ions. The antimicrobial activity, useful lifetime, halide ion level, and recycling possibilities of the system were quantified on a laboratory scale. A design for a large-scale multifiltration system based on this polymer is proposed.

Biocidal efficacy, biofilm-controlling function, and controlled release effect of chloromelamine-based bioresponsive fibrous materials

In this study, 2-amino-4-chloro-6-hydroxy-s-triazine (ACHT) was synthesized through controlled hydrolysis of 2-amino-4,6-dichloro-s-triazine (ADCT). A simple pad-dry-cure approach was employed to immobilize ACHT onto cellulosic fibrous materials. After treatment with diluted chlorine bleach, the covalently bound ACHT moieties were transformed into chloromelamines. The structures of the samples were fully characterized with NMR, UV/VIS, DSC, TG, iodometric titration and elemental analyses. The chloromelamine-based fibrous materials provided potent, durable, and rechargeable biocidal functions against bacteria (including multi-drug resistant species), yeasts, viruses, and bacterial spores. SEM studies demonstrated that the new fibrous materials could effectively prevent the formation of biofilms, and controlled release investigations in vitro suggested that the biocidal activities were bioresponsive. Biocidal mechanisms of the chloromelamine-based fibrous materials were further discussed.

Infection-resistant nonleachable materials for urologic devices

Bacterial colonization is the primary clinical problem faced by the surgeon and medical device innovator. Despite the absence of effective systemic treatment, medical implants and devices have been deployed with increasing success over the past five decades. Infection-resistant materials (IRMs) are a relatively recent addition to the science of implant and device development. The first IRM utilized leachable antimicrobial agents. Nonleachable technologies are being developed, some of which have the potential to make organ replacement even more successful in the future.