Lista wynalazków

Hybrid antimicrobial particles and the process for their production

autorzy: Tanţa Verona IORDACHE, Anamaria ZAHARIA, Andrei SÂRBU, Anita RADU, Ana Mihaela GAVRILĂ, Teodor SANDU, Elena Bianca STOICA, Steluţa APOSTOL

Human and environmental hazards caused by exposure to pathogenic bacteria originated from waste waters (WW) are some of the main global issues. WW are also contaminated by antibiotics or other pollutants and, hence, pathogens gain resistance to survive during the treatment. As a result, pathogen bacteria can be also found in soils, fresh water bodies or crops. Recent studies have revealed that antimicrobial polymeric materials provide a solution that addresses these problems with both superior antimicrobial efficacy and reduced toxicity, particularly materials including quaternary ammonium groups (QAS). The invention relates to obtaining new hybrid antimicrobial particles with applications in environmental and health protection and the process for their production. In order to create quaternary ammonium-functionalized-kaolin microparticles with antimicrobial effect, we grafted the QAS on the surface of kaolinite microparticles by a three-step procedure: (i) the intercalation of dimethyl sulfoxide (DMSO) molecules in the kaolinite layer (K) in order to increase the interlayer space and to make it accessible for further organic chemical grafting; (ii) chemical modification of kaolin intercalated with DMSO (K-D) with a silane monomer containing vinyl groups vinyltrimethoxysilane (VTMS)/ vinyltriethoxysilane (VTES); and (iii) free-radical polymerization of a quaternary ammonium salts with vinylbenzyl-trimethylammonium chloride (VBTAC). Chemical indicators, chemical oxygen demand (COD) and total phosphorous (TP), associated with the disinfection process were lower with approximately 15% and 42%, respectively, after treatment with the functionalized microparticles (vs. the initial WW sample). Although, kaolin alone presented a good bactericidal activity against Gram-negative bacteria such as E. Coli, the bacteriological indicators of the quaternary ammonium-functionalized-kaolin microparticles have indicated that such materials particularly contribute to the reduction of coliforms, C. perfringens but also E coli O157 by 82%, 65% and 67% respectively.