The dissolution mechanism of potential new biomarkers for medical diagnostics, based on lanthanide-doped NaYF4 nanoparticles, was presented. The studied nanoparticles dissolve partly in water due to the surface hydrolysis while they dissolve substantially in phosphate buffer. The driving force for this dissolution is the formation of stable and poorly soluble lanthanide phosphates. The reported findings are important for future development of NaYF4-based nanoparticles for in-vivo applications. Namely, phosphates are present in nucleic acids, ATP and cell membranes, from where they could be depleted due to the interaction with NaYF4 nanoparticles.
COBISS.SI-ID: 29679655
Influence of the hydrothermal conditions on physical and chemical properties of magnetic iron oxide nanoparticles was systematically studied. Method developed is based on co-precipitation of iron cations in aqueous media in the presence of ricinoleic acid followed by hydrothermal treatment of the precipitate. Concentration of ricinoleic acid and the temperature of hydrothermal treatment have strong influence on the average size of iron oxide nanoparticles. Relatively large amounts of magnetic iron oxide nanoparticles with a uniform size distribution in the size range between 8 nm and 24 nm can be synthesized. Nanoparticles are comparable with nanoparticles synthesized using complex synthetic procedures in expensive organic media at significantly higher temperatures. The magnetic iron oxide nanoparticles in the mentioned size range are suitable for applications in biomedicine. We have shown that the synthesized nanoparticles exhibit suitable magnetic properties for their application in magnetic hyperthermia treatment of cancer.
COBISS.SI-ID: 29840423
Understanding the adsorption of amino acids (AAs) onto magnetic iron-oxide nanoparticles (SPIONs) is important not only for the preparation of the aqueous suspensions, but also for understanding the interactions at the bio-nano interface. In the article the adsorption of aspartic acid (Asp) and lysine (Lys) onto SPIONs was explained, based on a characterization of the suspension properties and by direct HPLC analysis of the AA. On contrary to general opinion from the scientific literature our results showed that the AAs adsorb onto the SPIONs in the form of large molecular associates, which decisively influence the nanoparticles’ surface properties. The molecular associates are already formed in the AA aqueous solutions.
COBISS.SI-ID: 1537055939
A ferromagnetic suspension in an isotropic media is presented for the first time in this article. The basis for this development are magnetic nanoplates of Ba hexaferrite. The synthesis of the Ba hexaferrite nanoplates and the preparation of their suspensions were developed at in the frame of this Programme P2-0089. Butanol suspensions with high enough concentration of the nanoplates behave similar to ferromagnetic liquid-crystal suspensions, which were also developed with our participation. However, the unique property of the ferromagnetic suspensions in isotropic solvents is related their extremely high sensitivity to a magnetic field. Namely, these suspensions are sensitive to Earth's magnetic field, which makes them suitable for liquid magnetic-field sensors.
COBISS.SI-ID: 29253927
A new method for magnetic separation of lactic acid bacteria (LAB) O. oeni at a certain stage of the malolactic fermentation (MLF) in wine was developed. The method includes bonding of functionalized magnetic nanoparticles (MNPs) onto bacteria cell membranes in the suspensions, application of the “magneto responsive” bacteria in the fermentation and their magnetic separation from wine using the high gradient magnetic separation (HGMS). The research has shown that the MNPs attached at the cell surface did not influence on the O. oeni metabolism. By using HGMS, the O. oeni with the attached magnetic nanoparticles were efficiently removed from the fermentation media resulted in complete stop of the fermentation process at a certain, desired stage.
COBISS.SI-ID: 4977768