20.500.12556/RUL-133732 Magneto-liposomes as MRI contrast agents a systematic study of different liposomal formulations The majority of the clinically approved iron oxide nanoparticles (IO NPs) used as contrast agents for magnetic resonance imaging (MRI) have been withdrawn from the market either due to safety concerns or lack of profits. To address this challenge, liposomes have been used to prepare IO-based T$_2$ contrast agents. We studied the influence of different phospholipids on the relaxivity (r$_2$) values of magneto-liposomes (MLs) containing magnetic NPs in the bilayer, where a strong correlation between the bilayer fluidity and r$_2$ is clearly shown. Embedding 5-nm IO NPs in the lipid bilayer leads to a significant improvement in their relaxivity, where r$_2$ values range from 153 ± 5 s$^{−1}$ mM$^{−1}$ for DPPC/cholesterol/DSPE-PEG (96/50/4) up to 673 ± 12 s$^{−1}$ mM$^{−1}$ for DOPC/DSPE-PEG (96/4), compared to “free” IO NPs with an r$_2$ value of 16 s$^{−1}$ mM$^{−1}$, measured at 9.4 T MRI scanner. In vitro MRI measurements, together with the ICP-MS analysis, revealed MLs as highly selective contrast agents that were preferentially taken up by cancerous T24 cells, which led to an improvement in the contrast and an easier distinction between the healthy and the cancerous cells. A careful selection of the lipid bilayer to prepare MLs could offer efficient MRI contrast agents, even at very low IO NP concentrations. liposomes magnetic resonance imaging iron oxide contrast agent true false true Angleški jezik Ni določen Članek v reviji 2021-12-13 09:42:01 2021-12-13 09:42:01 2022-09-13 03:52:24 0000-00-00 00:00:00 2020 0 0 18 str. iss. 5, art. 889 Vol. 10 2020 0000-00-00 Zaloznikova Objavljeno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 537 2079-4991 10.3390/nano10050889 14045955 RAZ_Kostevsek_Nina_2020.pdf RAZ_Kostevsek_Nina_2020.pdf 1 6903C41690F1FFB7509684F1DB463CD4 288a3aef08885485ce17ca0baa8e7f56dcbe5b951b1f293354141ed00f69665a 7f9a51b3-5bf1-11ec-abdb-00155dcfd717 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=152042 https://www.mdpi.com/2079-4991/10/5/889 0 78635062-5bf1-11ec-abdb-00155dcfd717 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=152041 Medicinska fakulteta 0 0 0