284 KB29 KB199820252014Crnjac, AntonHeržič, KatjaHojnik Podrepšek, GordanaHojski, AljažKnez, ŽeljkoLeitgeb, Majaštevilka:1letnik:61str. 145-152ISSN:1318-0207COBISSID:4955199URN:URN:NBN:SI:doc-VYITAVWOenSlovensko kemijsko društvoActa chimica slovenicabiološko aktivne snovibiosubstancehitozanmagnetni mikrodelcimagnetni nanodelcitoksikološki testiToxicity of magnetic chitosan micro and nanoparticles as carriers for biologically active substances|Nanoparticles of inorganic magnetic core surrounded by layers of functional coatings are potential representatives of nanostructures for immobilization of bio-substances. Magnetic nanoparticles (MNPs) are often bound in aggregates due to a strong magnetic dipole, which has a lot of advantages, such as large surface area for binding biologically active substances. Chitosan is a polysaccharide polymer that is non-toxic, hydrophilic, biocompatible and has hydroxy and amino groups in its structure. Because of these chemical and biological properties it is a desirable bio-product for immobilization of enzymes and for binding of other biologically active substances. Magnetic micro and nanoparticles were synthesized with chitosan by three different methods; microemulsion process, suspension cross-linking technique and covalent binding of chitosan. Toxic effect of the prepared magnetic particles was determined as well and was examined on five different bacterial cultures; Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Enterococcus faecalis and Klebsiella pneumoniae. At concentrations of 10-30 mg of magnetic particles per 0.5 McFarland Standard solution of E. coli and per 400 CFU of S. aureus, P. aeruginosa, E. faecalis in K. pneumonia, no inhibition on the chosen bacterial cultures was detectedNanodelci iz magnetnega anorganskega jedra, oblečeni z večslojno funkcionalno prevleko, predstavljajo pomemben razred nanostrukturiranih delcev za vezavo biosubstanc. Zaradi možnega magnetnega dipola se magnetni nanodelci pogosto združujejo v skupke, kar pa ima številne prednosti, kot na primer velika površina, na katero lahko pritrdimo različne biološke komponente. Hitozan je polisaharidni polimer, ki je nestrupen, hidrofilen, biokompatibilen in vključuje prisotnost hidroksilne in amino skupine v svoji strukturi. Zaradi naštetih kemijskih in bioloških lastnosti spada hitozan med zaželjene biomateriale za imobilizacijo encimov in vezavo drugih biološko aktivnih substanc. Magnetne nanodelce, prevlečene s hitozanom, smo pripravili po treh različnih postopkih; s postopkom mikroemulzije, s postopkom suspenzijske zamreževalne tehnike ter s postopkom kovalentne vezaven hitozana. Toksikološke vplive pripravljenih magnetnih delcev smo preverili na petih različnih bakterijskih kulturah; Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Enterococcus faecalis in Klebsiella pneumoniae. Pri koncentracijah 10-30 mg magnetnih delcev na 0.5 McFarland standardne raztopine bakterijske kulture E.coli in na 400 CFU bakterijskih kultur S. aureus, P. aeruginosa, E. faecalis in K. pneumonia do inhibicije rasti mikroorganizmov ni prišloTEXTznanstveno časopisjejournalsSlovenian National E-content AggregatorNational and University Library of SloveniaSlovensko kemijsko društvo