Covalent and non-covalent strategies for surface modification of different textile materials with antimicrobial properties

Nowadays, millions of people become infected with bacteria that cause hospital infections, which is a major cause of mortality in hospitals, killing 700,000 people per year in the world. It is even projected that the number of deaths in hospitals will grow to 10 million by 2050. The use of antimicrobial textiles, especially in close contact with the patients and in the immediate and non-immediate surroundings, may significantly reduce the risk of infections. However, they should possess broad spectrum biocidal properties, be safe for use and highly effective against antibiotic resistant microorganisms, including those that are commonly involved in hospital-acquired infections. Most nosocomial infections are primarily by opportunistic microorganisms, i. e., they rarely cause diseases in a healthy immune system, but seek to exploit any weaknesses in the body of immunocompromised patients, such as victims of burns, cancer patients or beddriden with open wounds, in order to cause infections. These strains have the ability to grow in any environment, present important virulence factors, and have resistance to a large variety of antibiotics. Several antimicrobial agents have been tested in textiles. Quaternary ammonium compounds, silver, polyhexamethylene biguanides and triclosan have been used, with limited success. They have powerful bactericidal activity, however, the majority have a reduced spectrum of microbial inhibition and may cause skin irritation, citotoxicity, ecotoxicity and bacterial resistance. In addition, its incorporation in the textiles reduces their activity substantially and limits availability. Moreover, the biocide can gradually lose activity during the use and textile repeated laundering. To overcome these disadvantages, natural compounds such as L-Cysteine (L-Cys), bacteriophages and antimicrobial peptides (AMPs), were tested in this work as antimicrobial agents for fibrous materials. As such, in a first approach we carried out studies in order to confer antimicrobial properties on textile and ...