Production of highly stable upconverting nanoparticles modified with xanthan gum and their long-term studies

• Published in: Journal of alloys and compounds 2023-02, Vol.933, p.167708, Article 167708
• Main Authors: Przybylska, Dominika, Grzyb, Tomasz
• Format: Article
• Language: English
• Subjects: Long-term stability of colloids; Nanoparticles modified with xanthan gum; Strontium-lutetium fluorides; Upconversion; Xanthan gum
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2022.167708

Upconverting nanoparticles (UCNPs) forming stable water colloids are essential for biology and medicine, where they can be applied for bioimaging, disease detection, and treatment. The stability of UCNPs’ morphology in the form of their water colloids is as crucial as their spectroscopic properties. An appropriate surface modification is usually required to improve the stability of UCNPs in water. This article presents the results of long-term studies under Sr0.54Lu0.36F2.5:Yb3+, Tm3+ UCNPs modified with xanthan gum (XG) used as a colloid stabilizer. XG changes the surface charge and facilitates further bioconjugation to other molecules. Our studies confirmed that the structural properties of Sr0.54Lu0.36F2.5:Yb3+, Tm3+ UCNPs, their composition, and their luminescence do not change for 28 weeks. [Display omitted] •A long-term study (28 weeks) of physicochemical properties of obtained UCNPs in colloidal form.•Method of surface modification with natural polymer, xanthan gum, as a ligand for simple bioconjugation with molecules.•The synthesis of the NPs with positive (without modification) or negative (modified with xanthan gum) surface charge.