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Med različnimi vrstami anorganskih nanodelcev so bili v zadnjih letih kot zelo obetavni za uporabo v biomedicini izpostavljeni superparamagnetni nanodelci železovega oksida. Običajno jih pripravimo v obliki vodnih disperzij, ki same po sebi niso fizikalno stabilne, kar predstavlja pomemben tehnološki izziv. Da bi izboljšali kemijsko, mikrobiološko in predvsem fizikalno stabilnost nanodelcev, raziskovalci v zadnjem času veliko pozornosti posvečajo razvoju metod za sušenje disperzij nanodelcev. Zato je bil namen magistrske naloge uporabiti tehnologijo elektrostatskega sukanja kot alternativno metodo za sušenje disperzij superparamagnetnih nanodelcev. Z namenom izdelave suhega produkta, ki bo omogočal hitro in enostavno dipergiranje v prečiščeni vodi in v katerem bodo nanodelci ohranili primarne lastnosti, smo izhodiščni disperziji superparamagnetnih nanodelcev pred elektrostatskim sukanjem dodali vodotopna polimera polietilenoksid in poloksamer 188 v masnem razmerju 1:1. S sistematičnim večanjem deleža superparamagnetnih nanodelcev v disperziji smo določili maksimalno vsebnost superparamagnetnih nanodelcev v produktu elektrostatskega sukanja, ki še omogoča uspešno redispergiranje. Uspešnost redispergiranja superparamagnetnih nanodelcev iz produkta elektrostatskega sukanja smo proučevali z vrednotenjem hidrodinamske velikosti, porazdelitve velikosti in zeta potenciala superparamagnetnih nanodelcev, medtem ko smo morfologijo produktov elektrostatskega sukanja vrednotili z vrstično elektronsko mikroskopijo in vsebnost superparmagnetnih nanodelcev ter vlage v produktih elektrostatskega sukanja s termogravimetrično analizo. Z opravljenimi raziskavami smo ugotovili, da je največja vsebnost superparamagnetnih nanodelcev v produktu elektrostatskega sukanja, ki še omogoča hitro in enostavno redispergiranje z ohranjenimi izhodiščnimi lastnostmi superparamagnetnih nanodelcev, 65 % (m/m). Nadalje smo proučili še vpliv koncentracije polimerov v disperziji za elektrostatsko sukanje na lastnosti produkta elektrostatskega sukanja in ugotovili, da koncentracija polimerov v disperziji za elektrostatsko sukanje pomembno vpliva tako na morfologijo produkta, kot tudi na uspešnost redispergiranja superparamagnetnih nanodelcev iz produkta elektrostatskega sukanja. Med proučevanimi koncentracijami polimerov v disperzij za elektrostatsko sukanje (24, 42 in 64 mg/mL) je koncentracija 42 mg/mL omogočila izdelavo produkta v obliki nanovlaken (z vozli), iz katerega so se superparamagnetni nanodelci najbolj učinkovito redispergirali. Among the various types of inorganic nanoparticles, superparamagnetic iron oxide nanoparticles have been identified as the most promising for use in biomedicine. They are usually prepared in the form of aqueous dispersions, which are not physically stable, representing an important technological challenge. In order to improve the chemical, microbiological and above all physical stability of nanoparticles, researchers have recently been paying a lot of attention to the development of methods for drying nanoparticle dispersions. The aim of this master’s thesis was to use electrospinning as an alternative method for drying superparamagnetic nanoparticle dispersions. With the aim of producing a dry product, which will be rapidly and easily dispersed in purified water and in which the nanoparticles will retain their initial properties, water-soluble polymers polyethylene oxide and poloxamer 188 in a 1:1 mass ratio were added to the initial dispersion of superparamagnetic nanoparticles before electrospinning. By systematically increasing the proportion of superparamagnetic nanoparticles in the dispersion, we determined the maximal content of superparamagnetic nanoparticles in the electrospun product, which can still be successfully redispersed. The efficiency of the reconstitution of superparamagnetic nanoparticles from the electrospun product was studied by evaluation of their hydrodynamic particle size, size distribution and zeta potential, while the morphology of the electrospun products was evaluated by scanning electron microscopy and the content of superparamagnetic nanoparticles and moisture in the electrospun products by thermogravimetric analysis. Based on the results, we have determined that the maximal content of superparamagnetic nanoparticles in the electrospun product, which can still be rapidly and easily reconstituted, while initial properties of superparamagnetic nanoparticles are preserved, is 65% (w/w). Furthermore, we investigated the influence of the polymer concentration in the electrospinning dispersion on the properties of the electrospun product. The results show that the polymer concentrations in the electrospinning dispersion significantly affects both, the morphology of the electrospun product and the efficiency of the reconstitution of superparamagnetic nanoparticles from the obtained electrospun product. Among the studied polymer dispersions for electrospinning (24, 42 and 64 mg/mL), the dispersion with concentration of 42 mg/mL enabled the production of nanofibers (with beads), from which superparamagnetic nanoparticles were most efficiently reconstituted. |
