Nanocomposites and nanomaterials
Peculiarities of stabilization of silver and copper nanoparticles by amino acid Tryptophan in bactericidal textile materials
Petrik I.S.1, Naumenko A.P.2, Eremenko A.M.*1
1 Chuiko Institute of Surface Chemistry of NAS of Ukraine, 17, General Naumov Street, Kyiv 03164, Ukraine. 
* E-mail:. annaerem@ukr.net
2 Taras Shevchenko National University of Kyiv, 64/13, Volodymyrska Street, Kyiv-01601, Ukraine.

It is known that Ag+, Cu+, and Cu2+ ions are very important in biological processes and are widely used as bactericidal and antifungal agents. Biomedical materials based on nano-sized particles (NPs) of silver, copper and their bimetallic composites (BMNPs) impregnated in cotton tissues with pronounced bactericidal properties, that can be used as an alternative to antibiotics, have been obtained by us earlier by simple and economical method. However, their should accompanied by a toxic effect on the body. In this paper, the possibilities of stabilizing the nanosized copper and silver particles in the structure of the cotton tissue by the amino acid Tryptophan (Trp), the application of which will reduce the toxic effect of metal NPs, are studied. Trp practically does not absorb on pure tissue, but in presence of silver NPs and especially BMNPs in the structure of cotton the binding of Trp sharply increased. The reason is that silver and copper ions form complexes with Trp by using of the amino and carboxylic groups, which is accompanied by the fluorescence quenching of Trp. When wetted the modified tissue with water, the effect of Trp fluorescence quenching is more pronounced. In contact with water, active ions release from the surface of both metal particles occurs due to oxidation of metals, which interact with unbound molecules Trp on the fabric, accompanied by a pronounced quenching effect of Trp fluorescence. The antimicrobial and antimycotic properties of cotton fabrics with nanosized silver and copper modified by amino acid Trp are studied.