{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,24]],"date-time":"2026-09-24T02:49:27Z","timestamp":1790218167523,"version":"4.1.0"},"reference-count":58,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2023,2,1]],"date-time":"2023-02-01T00:00:00Z","timestamp":1675209600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001824","name":"Czech Science Foundation","doi-asserted-by":"publisher","award":["21-04420S"],"award-info":[{"award-number":["21-04420S"]}],"id":[{"id":"10.13039\/501100001824","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Upconverting nanoparticles (UCNPs) are of particular interest in nanomedicine for in vivo deep-tissue optical cancer bioimaging due to their efficient cellular uptake dependent on polymer coating. In this study, particles, ca. 25 nm in diameter, were prepared by a high-temperature coprecipitation of lanthanide chlorides. To ensure optimal dispersion of UCNPs in aqueous milieu, they were coated with three different polymers containing reactive groups, i.e., poly(ethylene glycol)-alendronate (PEG-Ale), poly(N,N-dimethylacrylamide-co-2-aminoethylacrylamide)-alendronate (PDMA-Ale), and poly(methyl vinyl ether-co-maleic acid) (PMVEMA). All the particles were characterized by TEM, DLS, FTIR, and spectrofluorometer to determine the morphology, hydrodynamic size and \u03be-potential, composition, and upconversion luminescence. The degradability\/dissolution of UCNPs in water, PBS, DMEM, or artificial lysosomal fluid (ALF) was evaluated using an ion-selective electrochemical method and UV-Vis spectroscopy. The dissolution that was more pronounced in PBS at elevated temperatures was decelerated by polymer coatings. The dissolution in DMEM was relatively small, but much more pronounced in ALF. PMVEMA with multiple anchoring groups provided better protection against particle dissolution in PBS than PEG-Ale and PDMA-Ale polymers containing only one reactive group. However, the cytotoxicity of the particles depended not only on their ability to rapidly degrade, but also on the type of coating. According to MTT, neat UCNPs and UCNP@PMVEMA were toxic for both rat cells (C6) and rat mesenchymal stem cells (rMSCs), which was in contrast to the UCNP@Ale-PDMA particles that were biocompatible. On the other hand, both the cytotoxicity and uptake of the UCNP@Ale-PEG particles by C6 and rMSCs were low, according to MTT assay and ICP-MS, respectively. This was confirmed by a confocal microscopy, where the neat UCNPs were preferentially internalized by both cell types, followed by the UCNP@PMVEMA, UCNP@Ale-PDMA, and UCNP@Ale-PEG particles. This study provides guidance for the selection of a suitable nanoparticle coating with respect to future biomedical applications where specific behaviors (extracellular deposition vs. cell internalization) are expected.<\/jats:p>","DOI":"10.3390\/ijms24032724","type":"journal-article","created":{"date-parts":[[2023,2,1]],"date-time":"2023-02-01T02:52:02Z","timestamp":1675219922000},"page":"2724","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":28,"title":["Chemical and Colloidal Stability of Polymer-Coated NaYF4:Yb,Er Nanoparticles in Aqueous Media and Viability of Cells: The Effect of a Protective Coating"],"prefix":"10.3390","volume":"24","author":[{"given":"Mykhailo","family":"Nahorniak","sequence":"first","affiliation":[{"name":"Institute of Macromolecular Chemistry, Czech Academy of Sciences, Heyrovsk\u00e9ho n\u00e1m. 2, 160 00 Prague, Czech Republic"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Vitalii","family":"Patsula","sequence":"additional","affiliation":[{"name":"Institute of Macromolecular Chemistry, Czech Academy of Sciences, Heyrovsk\u00e9ho n\u00e1m. 2, 160 00 Prague, Czech Republic"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dana","family":"Marekov\u00e1","sequence":"additional","affiliation":[{"name":"Institute of Experimental Medicine, Czech Academy of Sciences, V\u00edde\u0148sk\u00e1 1083, 142 20 Prague, Czech Republic"},{"name":"Department of Neurosciences, Second Faculty of Medicine, Charles University, V \u00davalu 84, 150 06 Prague, Czech Republic"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9353-5842","authenticated-orcid":false,"given":"Petr","family":"Matou\u0161","sequence":"additional","affiliation":[{"name":"Center for Advanced Preclinical Imaging, First Faculty of Medicine, Charles University, Salmovsk\u00e1 3, 120 00 Prague, Czech Republic"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0588-6256","authenticated-orcid":false,"given":"Oleksandr","family":"Shapoval","sequence":"additional","affiliation":[{"name":"Institute of Macromolecular Chemistry, Czech Academy of Sciences, Heyrovsk\u00e9ho n\u00e1m. 2, 160 00 Prague, Czech Republic"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Viktoriia","family":"Oleksa","sequence":"additional","affiliation":[{"name":"Institute of Macromolecular Chemistry, Czech Academy of Sciences, Heyrovsk\u00e9ho n\u00e1m. 2, 160 00 Prague, Czech Republic"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9403-8688","authenticated-orcid":false,"given":"Magda","family":"Vosmansk\u00e1","sequence":"additional","affiliation":[{"name":"Department of Analytical Chemistry, University of Chemistry and Technology Prague, Technick\u00e1 5, Prague 6, 166 28 Prague, Czech Republic"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7622-5837","authenticated-orcid":false,"given":"Lucia","family":"Machov\u00e1 Urdz\u00edkov\u00e1","sequence":"additional","affiliation":[{"name":"Institute of Experimental Medicine, Czech Academy of Sciences, V\u00edde\u0148sk\u00e1 1083, 142 20 Prague, Czech Republic"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4644-9212","authenticated-orcid":false,"given":"Pavla","family":"Jendelov\u00e1","sequence":"additional","affiliation":[{"name":"Institute of Experimental Medicine, Czech Academy of Sciences, V\u00edde\u0148sk\u00e1 1083, 142 20 Prague, Czech Republic"},{"name":"Department of Neurosciences, Second Faculty of Medicine, Charles University, V \u00davalu 84, 150 06 Prague, Czech Republic"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1775-2394","authenticated-orcid":false,"given":"V\u00edt","family":"Herynek","sequence":"additional","affiliation":[{"name":"Center for Advanced Preclinical Imaging, First Faculty of Medicine, Charles University, Salmovsk\u00e1 3, 120 00 Prague, Czech Republic"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6907-9701","authenticated-orcid":false,"given":"Daniel","family":"Hor\u00e1k","sequence":"additional","affiliation":[{"name":"Institute of Macromolecular Chemistry, Czech Academy of Sciences, Heyrovsk\u00e9ho n\u00e1m. 2, 160 00 Prague, Czech Republic"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,2,1]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"5161","DOI":"10.1021\/cr400425h","article-title":"Upconversion nanoparticles: Design, nanochemistry, and applications in theranostics","volume":"114","author":"Chen","year":"2014","journal-title":"Chem. 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