A Hidroxiapatita: um estudo computacional sobre os efeitos da dopagem com íons európio
Hydroxyapatite: a computational study on the effects of europium ion doping
DOI:
https://doi.org/10.13102/cad.fs.uefs.v24i01.13262Resumo
A Hidroxiapatita (Ca₁₀(PO₄)₆(OH)₂), devido à sua alta biocompatibilidade e similaridade estrutural com os tecidos ósseos, é amplamente utilizada como nanobiomaterial em aplicações ortopédicas e odontológicas. Neste capítulo, são apresentados resultados de simulações atomísticas voltadas à investigação dos efeitos da dopagem com íons európio (Eu³⁺) na matriz cristalina da Hidroxiapatita. As simulações foram conduzidas utilizando o código GULP 6.0, com base em potenciais interatômicos ajustados empiricamente e no modelo de casca de Dick–Overhauser, empregando a aproximação de Mott–Littleton para o tratamento dos defeitos extrínsecos. Os parâmetros estruturais obtidos apresentaram excelente concordância com os dados experimentais, validando o modelo adotado. Os cálculos das constantes elásticas revelaram estabilidade mecânica compatível com a fase hexagonal da HAp. Quanto à dopagem, os resultados indicaram que o íon Eu³⁺ tende a ocupar preferencialmente os sítios de cálcio, sendo compensado por hidroxilas intersticiais, enquanto os mecanismos de defeito associados à substituição em sítios de fósforo mostraram-se energeticamente desfavoráveis. Esses resultados contribuem para a compreensão teórica dos processos de dopagem em apatitas e reforçam o papel da simulação computacional como ferramenta poderosa na previsão das propriedades estruturais e mecânicas de materiais cerâmicos de interesse biomédico.
Downloads
Referências
Andronescu, E. et al. (2019) ‘Photoluminescent hydroxylapatite: Eu3+ doping effect on biological behaviour’, Nanomaterials [Preprint]. Available at: https://doi.org/10.3390/nano9091187.
Barta, C.A. et al. (2007) ‘Lanthanide containing compounds for therapeutic care in bone resorption disorders’, Journal of the Chemical Society. Dalton Transactions [Preprint]. Available at: https://doi.org/10.1039/b705123a.
Bottrill, M., Kwok, L. and Long, N.J. (2006) ‘Lanthanides in magnetic resonance imaging’, Chemical Society Reviews [Preprint]. Available at: https://doi.org/10.1039/b516376p.
DeLoach, L.D. et al. (1994) ‘Vibrational structure in the emission spectra of Yb3+-doped apatite crystals’, Journal of Lumines-cence [Preprint]. Available at: https://doi.org/10.1016/0022-2313(94)90013-2.
Dick, B.G. and Overhauser, A.W. (1958) ‘Theory of the Dielectric Constants of Alkali Halide Crystals’, Physical Review [Pre-print]. Available at: https://doi.org/10.1103/PhysRev.112.90.
Du, Z. and De Leeuw, N.H. (2004) ‘A combined density functional theory and interatomic potential-based simulation study of the hydration of nano-particulate silicate surfaces’, Surface Science [Preprint]. Available at: https://doi.org/10.1016/j.susc.2004.02.001.
Elliott, J.C. (1994) ‘Structure and chemistry of the apatites and other calcium orthophosphates’, Studies in Organic Chemistry [Preprint].
Fleet, M.E. and Pan, Y. (1994) ‘Site preference of nd in fluorapatite [Ca10(PO4)6F2]’, Journal of Solid State Chemistry [Preprint]. Available at: https://doi.org/10.1006/jssc.1994.1268.
Gale, J.D. (1997) ‘GULP: A computer program for the symmetry-adapted simulation of solids’, Journal of the Chemical Society - Faraday Transactions [Preprint]. Available at: https://doi.org/10.1039/a606455h.
Gu, M. et al. (2022) ‘Recent progress of rare earth doped hydroxyapatite nanoparticles: Luminescence properties, synthesis and biomedical applications’, Acta Biomaterialia [Preprint]. Available at: https://doi.org/10.1016/j.actbio.2022.06.006.
Hauptmann, S. et al. (2003) ‘Potential energy function for apatites’, Physical Chemistry Chemical Physics [Preprint]. Available at: https://doi.org/10.1039/b208209h.
Hughes, J.M., Cameron, M. and Crowley, K.D. (1989) ‘Structural variations in natural F, OH, and Cl apatites’, American Miner-alogist [Preprint].
Ignjatović, N.L. et al. (2019) ‘Rare-earth (Gd3+,Yb3+/Tm3+, Eu3+) co-doped hydroxyapatite as magnetic, up-conversion and down-conversion materials for multimodal imaging’, Scientific Reports [Preprint]. Available at: https://doi.org/10.1038/s41598-019-52885-0.
Jagannathan, R. and Kottaisamy, M. (1995) ‘Eu3+ luminescence: A spectral probe in M5(PO 4)3X apatites (M=Ca or Sr; X=F-, Cl -, Br- or OH-)’, Journal of Physics: Condensed Matter [Preprint]. Available at: https://doi.org/10.1088/0953-8984/7/44/014.
Kattimani, V.S., Kondaka, S. and Lingamaneni, K.P. (2016) ‘Hydroxyapatite–-Past, Present, and Future in Bone Regeneration’, Bone and Tissue Regeneration Insights, 7, p. BTRI.S36138. Available at: https://doi.org/10.4137/BTRI.S36138.
Katz, J.L. and Ukraincik, K. (1971) ‘On the anisotropic elastic properties of hydroxyapatite’, Journal of Biomechanics [Preprint]. Available at: https://doi.org/10.1016/0021-9290(71)90007-8.
Kaur, M. and Singh, K. (2019) ‘Review on titanium and titanium based alloys as biomaterials for orthopaedic applications’, Ma-terials Science and Engineering C [Preprint]. Available at: https://doi.org/10.1016/j.msec.2019.04.064.
Kröger, F.A. and Vink, H.J. (1954) ‘The Origin of the Fluorescence in Self‐Activated ZnS, CdS, and ZnO’, The Journal of Chemi-cal Physics, 22(2), pp. 250–252. Available at: https://doi.org/10.1063/1.1740044.
Lee, W.T., Dove, M.T. and Salje, E.K.H. (2000) ‘Surface relaxations in hydroxyapatite’, Journal of Physics Condensed Matter [Preprint]. Available at: https://doi.org/10.1088/0953-8984/12/48/302.
de Leeuw, N.H. (2001) ‘Local ordering of hydroxy groups in hydroxyapatite’, Chemical Communications [Preprint]. Available at: https://doi.org/10.1039/b104850n.
De Leeuw, N.H., Bowe, J.R. and Rabone, J.A.L. (2007) ‘A computational investigation of stoichiometric and calcium-deficient oxy- and hydroxy-apatites’, in Faraday Discussions. Available at: https://doi.org/10.1039/b602012g.
Liu, W. et al. (2025) ‘Application of Hydroxyapatite Composites in Bone Tissue Engineering: A Review’, Journal of Functional Biomaterials, 16(4), p. 127. Available at: https://doi.org/10.3390/jfb16040127.
Lucena, J.L. d. O. et al. (2026) ‘Intrinsic and Eu-doping defects, crystal field behavior, and surface morphology in ZnAl2O4: In-sights from atomistic modeling and spectroscopic analysis’, Journal of Physics and Chemistry of Solids, 208, p. 113135. Available at: https://doi.org/10.1016/j.jpcs.2025.113135.
Lucena, J.L.O. et al. (2026) ‘A computational study of the defect, doping, reduction process and spectroscopic study of the Zn2GeO4:Eu’, Journal of Luminescence, 289, p. 121595. Available at: https://doi.org/10.1016/j.jlumin.2025.121595.
Martin, P. et al. (1999) ‘Mechanisms involved in thermal diffusion of rare earth elements in apatite’, Journal of Nuclear Materials [Preprint]. Available at: https://doi.org/10.1016/S0022-3115(99)00126-9.
Meyers, M.A., Mishra, A. and Benson, D.J. (2006) ‘Mechanical properties of nanocrystalline materials’, Progress in Materials Sci-ence [Preprint]. Available at: https://doi.org/10.1016/j.pmatsci.2005.08.003.
Mostafa, N.Y. and Brown, P.W. (2007) ‘Computer simulation of stoichiometric hydroxyapatite: Structure and substitutions’, Journal of Physics and Chemistry of Solids [Preprint]. Available at: https://doi.org/10.1016/j.jpcs.2006.12.011.
Mott, N.F. and Littleton, M.J. (1938) ‘Conduction in polar crystals. I. Electrolytic conduction in solid salts’, Transactions of the Faraday Society [Preprint]. Available at: https://doi.org/10.1039/TF9383400485.
Neacsu, I.A. et al. (2019) ‘Luminescent hydroxyapatite doped with rare earth elements for biomedical applications’, Nano-materials [Preprint]. Available at: https://doi.org/10.3390/nano9020239.
Pedone, A. et al. (2007) ‘An ab initio parameterized interatomic force field for hydroxyapatite’, Journal of Materials Chemistry [Preprint]. Available at: https://doi.org/10.1039/b617858h.
Predoi, D. et al. (2007) ‘Hydroxyapatite-iron oxide bioceramic prepared using nano-size powders’, in Journal of Optoelectronics and Advanced Materials.
Rabone, J.A.L. and De Leeuw, N.H. (2006) ‘Interatomic potential models for natural apatite crystals: Incorporating strontium and the lanthanides’, Journal of Computational Chemistry [Preprint]. Available at: https://doi.org/10.1002/jcc.20323.
Santos, R.D.S. et al. (2022) ‘Effects of rare-earth doping and reduction processes in LiCaPO4 compound: A computer simulation study’, Journal of Solid State Chemistry [Preprint]. Available at: https://doi.org/10.1016/j.jssc.2021.122769.
Santos, R.D.S. and Rezende, M.V. dos S. (2014) ‘Atomistic Simulation of Intrinsic Defects and Trivalent and Tetravalent Ion Doping in Hydroxyapatite’, Advances in Condensed Matter Physics, 2014, pp. 1–8. Available at: https://doi.org/10.1155/2014/609024.
Santos, R.D.S. and Rezende, M.V.D.S. (2017) ‘Doping disorder and the reduction-doping process in LiSrPO4’, Physical Chemis-try Chemical Physics [Preprint]. Available at: https://doi.org/10.1039/c7cp04566b.
Shannon, R.D. and Prewitt, C.T. (1970) ‘Revised values of effective ionic radii’, Acta Crystallographica Section B Structural Crystallography and Crystal Chemistry, 26(7), pp. 1046–1048. Available at: https://doi.org/10.1107/S0567740870003576
Shi, D. et al. (2006) ‘Luminescent carbon nanotubes by surface functionalization’, Advanced Materials [Preprint]. Available at: https://doi.org/10.1002/adma.200501680.
Silva, C.H.P. et al. (2025) ‘A computational approach of the influence of Eu3+ doping on the optical properties of Na2MSiO4 (M = Mg, Zn) compound’, Journal of Luminescence, 288, p. 121542. Available at: https://doi.org/10.1016/j.jlumin.2025.121542.
Snyders, R. et al. (2007) ‘Experimental and ab initio study of the mechanical properties of hydroxyapatite’, Applied Physics Let-ters, 90(19). Available at: https://doi.org/10.1063/1.2738386.
Tanaka, Y. et al. (2010) ‘Effect of ionic polarization on crystal structure of hydroxyapatite ceramic with hydroxide nonstoichiom-etry’, Funtai Oyobi Fummatsu Yakin/Journal of the Japan Society of Powder and Powder Metallurgy [Preprint]. Available at: https://doi.org/10.2497/jjspm.57.520.
Ternane, R. et al. (1999) ‘Luminescent properties of Eu3+ in calcium hydroxyapatite’, Journal of Luminescence [Preprint]. Avail-able at: https://doi.org/10.1016/S0022-2313(98)00172-0.
Venkatesan, J. and Kim, S.-K. (2014) ‘Nano-Hydroxyapatite Composite Biomaterials for Bone Tissue Engineering—A Review’, Journal of Biomedical Nanotechnology, 10(10), pp. 3124–3140. Available at: https://doi.org/10.1166/jbn.2014.1893.
Webster, T.J. et al. (2004) ‘Osteoblast response to hydroxyapatite doped with divalent and trivalent cations’, Biomaterials [Pre-print]. Available at: https://doi.org/10.1016/j.biomaterials.2003.09.001.
Yang, P. et al. (2008) ‘Bioactive, luminescent and mesoporous europium-doped hydroxyapatite as a drug carrier’, Biomaterials [Preprint]. Available at: https://doi.org/10.1016/j.biomaterials.2008.07.042.
Zavala-Sanchez, L.A. et al. (2015) ‘Distribution of Eu2+ and Eu3+ Ions in Hydroxyapatite: A Cathodoluminescence and Raman Study’, ACS Biomaterials Science and Engineering [Preprint]. Available at: https://doi.org/10.1021/acsbiomaterials.5b00378.
Downloads
Publicado
Como Citar
Edição
Seção
Licença
Copyright (c) 2026 Ricardo Daniel Soares Santos, Wellisson Santos Silveira
Este trabalho está licenciado sob uma licença Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.
