Nanocomposites and nanomaterials

Antimicrobial activity of transcarpathian clinoptilolite modified with salts of transition metals
Gromyko O. M.1, Vasylechko V. O.1,2, Gryshchouk G. V.1, Roman I. I.1, Kalychak Ya. M.1, Fedorenko V. O.1, Bagday S. R.1
1Department of Genetic and Biotechnology, Department of Analytical Chemistry Ivan Franko National University of Lviv. 1 Universytetska Str., 4, 79000 Lviv, Ukraine. 
E-mail: vasylechko@ukr.net
2Department of Food Technology, Lviv University of Trade and Economics, 9 Samchuka Str., 79011 Lviv, Ukraine

The antimicrobial properties of highly dispersed (particle size  100 μm) Ukrainian transcarpathian clinoptilolite (CL) compositions with transition metal ions such as Mn2+ (Mn-CL), Cu2+ (Cu-CL) and Co2+ (Co-CL) were studied. The concentration of metal ions in the compositions: Mn2+ - 560 μg/g, Cu2+ - 670 μg/g, Co2+ - 1800 g/g.
Bacterial and yeast strains including Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 25923, and Candida albicans ATCC 885-653 were used as indicator pathogens. Antibacterial activity was evaluated by incubation of indicator pathogens (1-2 × 105 cells per 1 ml of solution) for 2 min in the presence of suitable compositions in concentrations 0.1, 0.5, and 1.0 mg/ml. In fact, CL has a very weak antimicrobial effect. Cu-CL in increasing concentrations delayed the growth of S. aureus from 50 to 35%, E. coli - from 17 to 3%, C. albicans - from 11 to 1%. Co-CL and Mn-CL had a stronger antimicrobial effect. In particular, at a maximum concentration (1.0 mg/ml), these compositions reduced the survival of S. aureus to 10-11%, E. coli - to 0.3-0.5%, C. albicans – 0.1-0.2%. Although the action of these compositions is weaker than the action of Ag-CL that was described earlier [1], they can be considered as a basis for the development of antimicrobial drugs for the treatment of skin lesions, in particular, due to their lower cost.

1.	Vasylechko V.O., Fedorenko V.O., Gromyko O.M., Gryshchouk G.V., Kalychak Ya.M., Zaporozhets O.A., Lototska M.T. Solid phase extractive preconcentration of silver from aqueous samples and antimicrobial properties of the clinoptilolite-Ag composite // Adsorpt Sci Technol. –2017. – 35(7-8). – Р. 602–611.