Antimicrobial polymers, also known as polymeric biocides, is a class of polymers with antimicrobial activity, or the ability to inhibit the growth of microorganisms such as bacteria, fungi or protozoans, as described in Wikepedia. These polymers have been engineered to mimic antimicrobial peptides which are used by the immune systems of living things to kill bacteria. Typically, antimicrobial polymers are produced by attaching or inserting an active antimicrobial agent onto a polymer backbone via an alkyl or acetyl linker. Antimicrobial polymers may enhance the efficiency and selectivity of currently used antimicrobial agents, while decreasing associated environmental hazards because antimicrobial polymers are generally nonvolatile and chemically stable. This makes this material a prime candidate for use in areas of medicine as a means to fight infection, in the food industry to prevent bacterial contamination, and in water sanitation to inhibit the growth of microorganisms in drinking water.
An antibacterial geopolymer, with potential in the construction industry has been developed. It is an inorganic resin that inhibits development, growth and reproduction of bacteria, yeasts and fungi; used as a cement, it can adhere to metal surfaces, ceramics or glass and inhibit harmful microorganisms. Researchers at the Universidad Michoacana de San Nicolás de Hidalgo (UMSNH) in Mexico used this antibacterial geopolymer called Antibac to repel pathogens. Dr. Jose Carlos Rubio is the creator of the technology.
The product can be placed on any surface just like a construction paste, setting in just 24 hours. It consists of clay and sea sand dissolved in an aqueous solution and a biocidal agent in the form of microscopic glass particles that inhibit bacterial growth. The inorganic resin, once solidified, traps the antibacterial microcrystals in a "cage," keeping them enclosed, but allowing the interaction with pathogens; these microorganisms, when contacting the geopolymer, get stuck due to its high affinity to the microcrystals, so no contact transference occurs with other materials. The microorganisms are then removed by existing diffusion or any simple cleaner. Moreover, the product is not harmful to the environment because during the manufacturing process, no volatile organic compounds are generated, only water vapor. He explained that the material has a duration of approximately 100 years, is resistant to acids and water, and does not discolor because it endures solar radiation. "The natural color is cream, but we can add any pigment and adapt it to the customer's needs." Its antibacterial effect makes it ideal for hospitals, restaurants or the food processing industry, but it can also be used in the home because it costs less than US$10 per square meter, making it cheap compared to current synthetic coatings.
A recent discovery could be an important breakthrough in the search for environmentally-friendly ways to control bacteria while preventing antibiotic resistance and resistant bacteria. Researchers at KTH Royal Institute of Technology in Stockholm have discovered an antibacterial polymer that can be used in everyday products such as sportswear, diapers and bandages, without causing resistant bacteria. "We have managed to find an antibacterial polymer that attaches stably to cellulose and therefore cannot be released into the environment," says Josefin Illergard, a chemistry researcher at KTH. Illergard says the team's discovery is based on cellulose fibres embedded in a polymer, which kills bacteria. Cellulose is the most common organic substance in nature and the primary structural component of plant cell walls. The active polymer is so strongly bonded to the fibres of the cellulose material that it does not loosen or leak into the environment via water. Antibacterial agents such as triclosan and silver ions are commonly used in sportswear and shoes to remove unpleasant odors from bacteria formation. But such biocides leak into the environment when the treated garments or surfaces are washed, raising the risk that bacteria will gradually become resistant to their effect. "If someone uses a cloth to wipe a countertop treated with antibacterial agents, and that cloth is rinsed in the sink, those substances are then spread further through the drain and into the environment where they can contaminate soil and water and give rise to bacterial resistance," Illergård says. Because polymer has a positive charge and bacteria a negative charge, the new material actually attracts bacteria, she says. The material does not contain large amounts of polymer; and only non-toxic nitrogen oxides remain after it is burned."In the future, I believe our material will be used in cleaning clothes, in sanitation for hospitals and in different kinds of water purification filters," she says.