16. - 18. 10. 2013, Brno, Czech Republic, EU USE OF THE SILVER PHOSPHATE NANOPARTICLES (SPNPs) FOR THEIR ANTIMICROBIAL EFFECT ON BACTERIAL STRAINS Dagmar CHUDOBOVA 1 , Kristyna CIHALOVA 1 , Branislav RUTTKAY-NEDECKY 1,2 , Pavel KOPEL 1,2 , Michal ZUREK 1 , Karel BASTL 1,3 , Vojtech ADAM 1,2 , and Rene KIZEK 1,2* 1 Department of Chemistry and Biochemistry, Faculty of Agronomy, Mendel University in Brno, Zemedelska 1, CZ-613 00 Brno, Czech Republic, European Union 2 Central European Institute of Technology, Brno University of Technology, Technicka 3058/10, CZ-616 00 Brno, Czech Republic, European Union 3 Vyzkumny ustav pletarsky, Sujanovo namesti 302/3, CZ-602 00 Brno, Czech Republic, European Union *Corresponding author Rene Kizek, Department of Chemistry and Biochemistry, Mendel University in Brno, Zemedelska 1, CZ-613 00 Brno, Czech Republic, European Union; E-mail: *kizek@sci.muni.cz Abstract Bacterial infections caused by Gram - or Gram + bacteria can be a serious complication in the treatment of many diseases. These strains are a common producer of nosocomial infections, which can be acquired in hospitals. The aim of many studies is to prevent these infections using various technical and technological procedures. For comparison of the antimicrobial effect of silver phosphate nanoparticles (SPNPs) in complexes with hyaluronic acid or chitosan on S. aureus and E. coli (8.0 * 10 7 KTJ/1 ml), minimal inhibition concentration (MIC) was determined. SPNPs with typical spherical structure (200-300 nm) and compact structure were prepared. MIC of S. aureus with complex of hyaluronic acid with SPNPs resulted from the concentration of 25 μM SPNPs and the total inhibition concentration (TIC) was 225 μM SPNPs. MIC of S. aureus with complex of chitosan with SPNPs was 10 μM SPNPs, and TIC was 25 μM SPNPs. In the case of E. coli bacterial culture with complex of hyaluronic acid with SPNPs was MIC determined at 10 μM SPNPs, and TIC was 150 μM SPNPs. Applied complex of chitosan with SPNPs has MIC 10 μM, which was the same as TIC. The best result was achieved at E. coli bacterial strain after the application of the complex of chitosan with SPNPs. Due to the increasing severity of the problem of resistance to commonly used antibiotic drugs, the study of the substances with antimicrobial effects, especially on the basis nanotechnologies, should be a priority in the future. Keywords: Silver phosphate nanoparticles; Hyaluronic acid; Chitosan; Antimicrobial effect 1. INTRODUCTION Metal nanoparticles have found, due to their antibacterial properties, application in medicine where bacterial sterility is required. Especially, during transplantations, implants represent a high risk of bacterial infection. To minimize this threat, the utilization of nanoparticles in combination with certain polymeric substances was found very effective [3, 4]. Complexes of polymer materials with silver nanoparticles are widely used as growth inhibitors G + and G - bacteria [13] and as substances utilized for posttraumatic or postoperative tissue regeneration applications [9, 16]. One of these polymers is chitosan, which has many useful properties such as biocompatibility, homeostatic activity and accelerates wound healing [4]. The polymeric structure of chitosan provides suitable binding area for silver nanoparticles [5] and therefore it has bactericidal effects in particular against Staphylococcus aureus and Escherichia coli [14, 15, 17, 18] combined with very low toxicity [12]. The exact mechanism of