Vrednotenje vpliva magnetnih nanodelcev z oblogo iz silicijevega dioksida na keratinocite in vitro

Kolenc, Lana (author), Kocbek, Petra (mentor), Dragar, Črt (co-mentor)

Nanotehnologija je hitro razvijajoče se področje, na katerem dandanes potekajo številne raziskave. Nanomateriali v primerjavi z materiali večjih dimenzij izkazujejo posebne fizikalne, biološke in kemijske lastnosti, zaradi katerih imajo velik potencial za uporabo v biomedicini. Za zelo obetavne nanomateriale veljajo magnetni nanodelci, ki se med drugim raziskujejo v namene diagnostike in zdravljenja rakavih obolenj s ciljano dostavo zdravilnih učinkovin. Kljub številnim prednostim eno izmed ovir za prehod magnetnih nanodelcev v klinično uporabo predstavlja njihova premalo raziskana varnost. Do danes je bilo sicer ugotovljeno, da lahko na varnost magnetnih nanodelcev pomembno vplivajo njihova velikost, oblika, sestava in površinske lastnosti, med katerimi pa se v zadnjem času kot pomembna lastnost izpostavlja morfologija površine magnetnih nanodelcev oz. velikost por na njihovi površini. Namen magistrske naloge je zato bil sistematično ovrednotiti vpliv morfologije površine magnetnih nanodelcev na keratinocite in vitro. V raziskavi smo kot magnetne nanodelce uporabili skupke superparamagnetnih nanodelcev železovega oksida z oblogo iz silicijevega dioksida z različno velikostjo por. Obloga je bila nemodificirana ali modificirana z molekulami polietilenglikola. Najprej smo magnetne nanodelce ovrednotili z vidika hidrodinamske velikosti delcev, naboja na površini in stabilnosti v prečiščeni vodi ter rastnem mediju za keratinocite. Nadalje smo keratinocite izpostavili magnetnim nanodelcem v časovnem obdobju od 24 h do 72 h in v koncentracijskem razponu od 25 µg/mL do 150 µg/mL ter ovrednotili vpliv magnetnih nanodelcev na morfologijo in adhezijo ter živost keratinocitov in vitro. Ugotovili smo, da magnetni nanodelci z večjimi porami v oblogi (premer por ~ 69 nm) bolj znižajo živost keratinocitov in vitro kot neporozni oz. magnetni nanodelci z manjšimi porami v oblogi (premer por ~ 12 nm). V naših poskusih se je izkazalo, da spremembe morfologije in adhezije keratinocitov po inkubiranju z magnetnimi nanodelci nakazujejo na zmanjšanje živosti keratinocitov. Nadalje smo ugotovili, da zaostanki reagentov iz sinteze obloge magnetnih nanodelcev, kot je na primer pozitivno nabita površinsko aktivna snov heksadeciltrimetilamonijev bromid, pomembno znižajo živost keratinocitov in vitro. Ugotovili smo tudi, da bi na dobljene rezultate poleg različne morfologije površine nanodelcev utegnili vplivati tudi drugi dejavniki, kot so agregiranje in posedanje magnetnih nanodelcev med inkubiranjem s keratinociti ter neželena interferenca magnetnih nanodelcev pri vrednotenju absorbance produkta pri valovni dolžini 490 nm. Z našimi odkritji smo kot prvi sistematično ovrednotili vpliv morfologije površine magnetnih nanodelcev na odziv celic v in vitro pogojih.

• Language: Slovenian
• Keywords: Keratinociti, magnetni nanodelci, obloga iz silicijevega dioksida, velikost por, živost celic
• Work type: Master's thesis/paper
• Organization: FFA - Faculty of Pharmacy
• Year: 2024
• PID: 20.500.12556/RUL-155764
• Publication date in RUL: 17.04.2024

Secondary language

• Language: English
• Title: Evaluation of silica-coated magnetic nanoparticle impact on keratinocytes in vitro

Abstract

Nanotechnology is a rapidly developing field that is under intensive investigation. In comparison to materials on a larger scale, nanomaterials show unique physical, biological, and chemical properties, because of which they show great potential for use in biomedicine. Particularly magnetic nanoparticles have proven to be very promising and are currently being investigated in the diagnostics and treatment of cancer by targeted drug delivery. However, despite their many advantages, the transition of magnetic nanoparticles into clinical use is hindered by their insufficiently investigated safety. To date, it has been established that the safety of magnetic nanoparticles can be significantly influenced by their size, shape, composition, and surface properties, among which the morphology of their surface, precisely the size of the pores on their surface, has recently been highlighted to have an important impact on the safety of magnetic nanoparticles. This thesis aimed to systematically evaluate the impact of surface morphology of silica-coated magnetic nanoparticles on keratinocytes in vitro. The magnetic nanoparticles used in this study were superparamagnetic iron oxide nanoparticle clusters coated with silica with different pore sizes. Additionally, the coating was unmodified or modified with polyethylene glycol molecules. Firstly, we evaluated the magnetic nanoparticles regarding their hydrodynamic size, surface charge, and stability in purified water and the keratinocyte growth medium. Next, we exposed the keratinocytes to magnetic nanoparticles for 24 h to 72 h in a concentration range of 25 µg/mL to 150 µg/mL and evaluated their impact on the keratinocyte morphology, adhesion, and viability in vitro. We determined that the magnetic nanoparticles with larger pores in the coating (pore diameter ~ 69 nm) reduce the viability of keratinocytes in vitro more than nonporous or magnetic nanoparticles with smaller pores in the coating (pore diameter ~ 12 nm). In our experiments we showed that changes in keratinocyte morphology and adhesion after incubation with magnetic nanoparticles were shown to correlate with reduced keratinocyte viability. We further proved that the impurities from the synthesis of the magnetic nanoparticles, such as positively charged surface-active ingredient hexadecyltrimethylammonium bromide, may have a significant effect on the keratinocyte viability in vitro. We have revealed that, in addition to the different surface morphologies of the nanoparticles, other factors could also influence our results, such as the aggregation and deposition of magnetic nanoparticles during incubation with keratinocytes and the interference of magnetic nanoparticles when evaluating the absorbance of the product at a wavelength of 490 nm. With our findings, we were the first to systematically evaluate the impact of the surface morphology of magnetic nanoparticles on cellular response in vitro.

• Keywords: Keratinocytes, magnetic nanoparticles, silicon dioxide coating, pore size, cell viability