DETVANOVÁ Lenka Mendel University Brno

Comparison of the Characteristics of Membranes with and without External Modification with Nanoparticles of Silver

Co-authors KALHOTKA Libor, PŘICHYSTALOVÁ Jitka, DOSTÁLOVÁ Lenka, DOŠEK Michal, LEV Jaroslav, KARLÍKOVÁ Martina

The aim of this study was to monitor antimicrobial abilities of filtration materials with and without the addition of silver. Microfiltering material SPURTEX with nanoparticles of silver, from SPUR a.s. Zlín was modified in Palacký University Olomouc - Regional Centre of Advanced Technologies and Materials. The modifications of membranes consisted of covalent bounding of Ag nanoparticles on the surface of the membrane through a polymeric linker. The advantages of this method are low service expenses and absence of potentially dangerous chemicals, which may be released into the water. Dimensions of membrane pores are ranged between 0,30 μm ± 0,12 μm, meaning that the selected membrane should be able to catch most of the microorganisms. Escherichia coli was selected for the simulation of microbiological contamination. This bacterium is an indicator of fecal contamination and its occurrence in water is very strictly monitored. The spreading of this bacterium in a human being is the cause of a range of digestive and urogynaecological diseases. 100ml of contaminated water was filtrated at a pressure of 0,5 bar through a filtration device, which is made from anticorrosive steel and was sterilised before the experiment. For every sample, parameters of filtration were determined (filtration time, amount of bacteria before and after filtration, efficiency of filtration, etc.). In the samples, Escherichia coli on VRBL agar (Biokar Diagnostics, France) was determined using the plate cultivation method during 24 h at a temperature of 37 ˚C. The methods of the experiment are based on ČSN EN ISO 9308-1. The results of laboratory experiments shows materials with surface modification of Ag have a better microbiological characteristic. A more detailed description and results are in the experimental and methodological part of this submission.