Chemical binding of chitosan nanoparticles onto oxidised cellulose

Namen diplomskega dela je bil uspešno kemijsko vezati hitozan in hitozanske nanodelce na oksidirano celulozo. Oksidirana celuloza omogoča vezna mesta za aminske skupine hitozana. Na ta način se predvideva bolj stabilna vezava hitozana na površino vlaken. Sposobnost adsorpcije hitozana in hitozanskih nanodelcev na površino materiala smo določili s FTIR spektroskopijo, kjer smo želeli dokazati tipične funkcionalne skupine celuloznih vlaken in hitozana. Z XPS spektroskopijo smo dobili podatke o kemijski sestavi površine vlaken, ki smo jih obdelali. Z gravimetrično metodo, pa smo na razliki mas pred in po obdelavi ugotovili koliko hitozana in hitozanskih nanodelcev se je vezalo na substrat. Analizirali smo tudi desorpcijo hitozana in hitozanskih nanodelcev, tako da smo preverili prisotnost celokupnega dušika (TN) v desorpcijski kopeli, medtem ko smo s polielektrolitskimi titracijami preverili prisotnost ostankov hitozana in hitozanskih nanodelcev v desorpcijski kopeli. Desoprcijo smo spremljali tudi z gravimetrično metodot.j. razliko mas pred in po desorpciji. Ugotovili smo, da se hitozan in hitozanski nanodelci v primerjavi z neoksidirano referenčno celulozo bolj uspešno kemijsko vežejo na oksidirano celulozo. Kljub vezavi aminskih skupin z negativnimi skupinami celuloze in posledično manjši protonaciji le teh, so tovrstno funkcionalizirana vlakna še vedno specifično protimikrobna.The aim of this study was successfully chemically bind chitosan and chitosan nanoparticles on cellulose and oxidized cellulose. The ability to absorb chitosan and chitosan nanoparticles was determined by FTIR spectroscopy, where we wanted to show the typical functional groups of cellulose fibers and chitosan. The XPS spectroscopy gave us information on the chemical composition of the fiber surface, which were treated with the gravimetric method, in which we had difference weight, before and after treatment and determine the amount of chitosan and chitosan nanoparticles that has binded to the substrate. We also checked desorption of chitosan and chitosan nanoparticles, with verifying of the presence of total nitrogen (TN) in the desorption bath, and with polyelectrolyte titrations tested for the presence of residues of chitosan and chitosan nanoparticles in the desorption bath. We also monitored the desorption with the gravimetric methodthe weight difference before and after desorption. We have found that the chitosan and chitosan nanoparticles in comparison with the reference non-oxidized cellulose efficiently chemically bind to the oxidized cellulose. Despite the binding of amine groups with the negative groups of cellulose and consequently smaller protonation of these, such functionalized fibers are still specific antimicrobials