N -bromo-hydantoin grafted polystyrene beads: Synthesis and nano-micro beads characteristics for achieving controlled release of active oxidative bromine and extended microbial inactivation efficiency

Preparation and efficacy of antibacterial methacrylate monomer-based polymethyl methacrylate bone cement containing N-halamine compounds

Introduction

Our objective in this study was to prepare a novel type of polymethyl methacrylate (PMMA) bone cement, analyze its material properties, and evaluate its safety and antibacterial efficacy.

Methods

A halamine compound methacrylate antibacterial PMMA bone cement containing an N-Cl bond structure was formulated, and its material characterization was determined with Fourier transform infrared spectroscopy (FT-IR) and 1H-NMR. The antibacterial properties of the material were studied using contact bacteriostasis and releasing-type bacteriostasis experiments. Finally, in vitro and in vivo biocompatibility experiments were performed to analyze the toxic effects of the material on mice and embryonic osteoblast precursor cells (MC3T3-E1).

Results

Incorporation of the antibacterial methacrylate monomer with the N-halamine compound in the new antibacterial PMMA bone cement significantly increased its contact and releasing-type bacteriostatic performance against Staphylococcus aureus. Notably, at 20% and 25% additions of N-halamine compound, the contact and releasing-type bacteriostasis rates of bone cement samples reached 100% (p < 0.001). Furthermore, the new antibacterial bone cement containing 5%, 10%, and 15% N-halamine compounds showed good biocompatibility in vitro and in vivo.

Conclusion

In this study, we found that the novel antibacterial PMMA bone cement with N-halamine compound methacrylate demonstrated good contact and releasing-type bacteriostatic properties against S. aureus. In particular, bone cement containing a 15% N-halamine monomer exhibited strong antibacterial properties and good in vitro and in vivo biocompatibility.

Multifunctional polymeric guanidine and hydantoin halamines with broad biocidal activity

Prolonged and excessive use of biocides during the coronavirus disease era calls for incorporating new antiviral polymers that enhance the surface design and functionality for existing and potential future pandemics. Herein, we investigated previously unexplored polyamines with nucleophilic biguanide, guanidine, and hydantoin groups that all can be halogenated leading to high contents of oxidizing halogen that enables enhancement of the biocidal activity. Primary amino groups can be used to attach poly(N-vinylguanidine) (PVG) and poly(allylamine-co-4-aminopyridine-co-5-(4-hydroxybenzylidene)hydantoin) (PAH) as well as a broad-spectrum commercial biocide poly(hexamethylene biguanide) (PHMB) onto a solid support. Halogenation of polymer suspensions was conducted through in situ generation of excess hypobromous acid (HBrO) from bromine and sodium hydroxide or by sodium hypochlorite in aqueous solutions, resulting in N-halamines with high contents of active > N-Br or > N-Cl groups. The virucidal activity of the polymers against human respiratory coronavirus HCoV-229E increased dramatically with their halogenation. Brominated PHMB-Br showed activation activity value > 5 even at 1 mg/L, and complete virus inhibition was observed with either PHMB-Br or PAH-Br at 10 mg/mL. Brominated PVG-Br and PAH-Br possessed fungicidal activity against C. albicans, while PHMB was fungistatic. PHMB, PHMB-Br and PAH polymers demonstrated excellent bactericidal activity against the methicillin-resistant S. aureus and vancomycin-resistant E. faecium. Brominated polymers (PHMB-Br, PVG-Br, PAH-Br) were not toxic to the HeLa monolayers, indicating acceptable biocompatibility to cultured human cells. With these features, the N-halamine polymers of the present study are a worthwhile addition to the arsenal of biocides and are promising candidates for development of non-leaching coatings.

Disinfectants role in the prevention of spreading the COVID ‐19 and other infectious diseases: The need for functional polymers!

The spreading of coronavirus through droplets and aerosols of an infected person is a well‐known mechanism. The main protection methods from this virus are using disinfectants/sanitizers, face masks, keeping social distance, and vaccination. With the rapid mutations of the virus accompanied by its features and contagions changing, new advanced functional materials development is highly needed. The usage of disinfectants/sanitizers in excess generates poisonous effects among the general public. Effective and simultaneously, human‐friendly sanitizers or disinfectants are required to prevent the poisoning and the associated issues. They minimize the toxic effects of the currently available materials by rapid action, high potential, long‐term stability, and excellent biocompatible nature. Here, we summarize the available antiviral materials, their features, and their limitations. We highlight the need to develop an arsenal of advanced functional antiviral polymers with intrinsic bioactive functionalities or released bioactive moieties in a controlled manner for rapid and long‐term actions for current and future anticipated viral outbreaks.

Antiviral Polymers Based on N-Halamine Polyurea

N-halamines are a commonly applied class of antimicrobial agents used for a variety of applications relating to human health. Here, we present the modulation of the common polymers polyurea and polyguanidine with the N-halamine technology. The N-H bonds in either polymer were converted to N-Cl or N-Br bonds capable of releasing Cl⁺ or Br⁺ cations to aqueous media as antiviral agents. Controlled release of the oxidizing agents was monitored for a period of 4 weeks. Antiviral activity was evaluated against the T4 bacteriophage as well as against the highly stable plant virus belonging to the Tobamovirus genus, tomato brown rugose fruit virus. The incorporation of the N-halamine technology on commonly used polymers has effectively introduced antiviral functionality for a wide variety of potential applications.

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.

Development of self-stratified antibacterial polymers via click chemistry

A new self-stratified contact-killing antimicrobial polyurethane was synthesized via efficient and orthogonal click-chemistry.

Antimicrobial Polymers in the Nano-World

Infections are one of the main concerns of our era due to antibiotic-resistant infections and the increasing costs in the health-care sector. Within this context, antimicrobial polymers present a great alternative to combat these problems since their mechanisms of action differ from those of antibiotics. Therefore, the microorganisms' resistance to these polymeric materials is avoided. Antimicrobial polymers are not only applied in the health-care sector, they are also used in many other areas. This review presents different strategies that combine nanoscience and nanotechnology in the polymer world to combat contaminations from bacteria, fungi or algae. It focuses on the most relevant areas of application of these materials, viz. health, food, agriculture, and textiles.