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. 2021 Sep;20(9):1195-1208.
doi: 10.1007/s43630-021-00092-0. Epub 2021 Aug 27.

Physiochemical characterization of highly biocompatible, and colloidal LaF3:Yb/Er upconversion nanoparticles

Anees A Ansari  1 , Abdul K Parchur  2 , Joselito P Labis  3 , Muhammad Ali Shar  3
Affiliations

Physiochemical characterization of highly biocompatible, and colloidal LaF3:Yb/Er upconversion nanoparticles

Anees A Ansari et al. Photochem Photobiol Sci. 2021 Sep.

Abstract

Highly colloidal upconversion nanoparticles (UCNPs) were synthesized at low temperatures by the thermal decomposition process. The structure, morphology, crystallinity, surface chemistry, and optical properties were systematically optimized and studied through various spectroscopic techniques. X-ray diffraction (XRD) patterns have shown the formation of single-phase, highly purified, well-crystalline, hexagonal LaF3 NPs, while the TEM micrographs show small, irregular sizes, spherically shaped, and aggregated polycrystalline UCNPs with an average crystalline size of about 8-15 nm. The Negative Zeta Potential value exhibits good biocompatibility of the UCNPs, which supports the idea that surface-anchored hydroxyl groups facilitate the stabilization of the NPs in aqueous media, as well as enhance biomolecules' tagging efficiency. The absorption spectrum, Zeta Potential, and hydrodynamic size that were measured in aqueous media illustrate excellent dispersibility, colloidal stability, biocompatibility, and cytotoxicity character of the UCNPs. Zeta potential and MTT assay studies illustrated high biocompatibility, it could be due to the surface-anchored hydroxyl groups. The nanoproduct demonstrates an excellent UC luminescence spectrum (i.e., prominent green emission 4S3/2 → 4I/15/2) upon irradiation by the 980-nm laser diode. TEM micrographs, further, revealed that this optically active material with aqueous sensitivities, porous crystal structure, and excellent UCNPs, could be a favorable candidate for potential photonics-based bio-related applications.

Keywords: Bandgap; Biocompatible; Colloidal; LaF3; Upconversion nanoparticles.

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References

    1. Meiser, F., Cortez, C., & Caruso, F. (2004). Biofunctionalization of fluorescent rare-earth-doped lanthanum phosphate colloidal nanoparticles. Angewandte Chemie. International Edition, 43(44), 5954–5957. - PubMed
    1. Ye, Z. Q., Tan, M. Q., Wang, G. L., & Yuan, J. L. (2004). Novel fluorescent europium chelate-doped silica nanoparticles: Preparation, characterization and time-resolved fluorometric application. Journal of Materials Chemistry, 14(5), 851–856.
    1. Wang, L. Y., & Li, Y. D. (2007). Luminescent nanocrystals for nonenzymatic glucose concentration determination. Chem-Eur J, 13(15), 4203–4207. - PubMed
    1. Vetrone, F., Naccache, R., Morgan, C. G., & Capobianco, J. A. (2010). Luminescence resonance energy transfer from an upconverting nanoparticle to a fluorescent phycobiliprotein. Nanoscale, 2(7), 1185–1189. - PubMed
    1. Abel, K. A., Qiao, H. J., Young, J. F., & van Veggel, F. C. J. M. (2010). Four-fold enhancement of the activation energy for nonradiative decay of excitons in PbSe/CdSe core/shell versus PbSe colloidal quantum dots. Journal of Physical Chemistry Letters, 1(15), 2334–2338.

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