Preparation of Eu3+/Gd3+ co-doped hydroxyapatite luminescent nanocrystals for cell labelling

Abstract

Event Abstract Back to Event Preparation of Eu3+/Gd3+ co-doped hydroxyapatite luminescent nanocrystals for cell labelling Yingchao Han1, 2, Yunfei Xie1, 2, Tsh Perera1, 3, Fang Li1, 2, Xinyu Wang1, 2 and Shipu Li1, 2 1 Wuhan University of Technology, State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, China 2 Wuhan University of Technology, Biomedical Materials and Engineering Research Center of Hubei Province, China 3 Sabaragamuwa University of Sri Lanka, Faculty of Applied Sciences, Sri Lanka Introduction: Hydroxyapatite (Ca10(PO4)6(OH)2, HAP), the inorganic component of bone and teeth of mammals, possesses excellent biocompatibility and bioactivity. The characteristic hexagonal structure and space group endow HAP with the ability for being easily substituted by rare earth (RE) ions and rare earth ions at Ca2+ site can emit specific luminescence. Therefore, nano RE-HAP attracted much attentions as cell labels due to its good biocompatibility and biodegradability. However, it is still required to further improve the luminescent signal of RE-HAP for cell labelling application. Herein, a route for enhancing the luminescence of RE doped HAP was studied based on the synergistic effect of different rare earth elements co-doping, avoiding the fluorescence quenching and cytotoxicity resulting from excess RE doping content, and the size increase and agglomeration resulting from calcinations at high temperature. Materials and Methods: Eu/Gd co-doped HAP was prepared by coprecipitation method. (NH4)2HPO4 solution were introduced into a mixed solution of Ca(NO3)2, EuCl3 and GdCl3 at 80 °C with the molar ratio of (Ca+Eu+Gd)/P of 1.67. Then, the pH value was adjusted to 9-10 using NH3·H2O. After violent stirring for 1 h, the obtained precipitations were recovered by centrifugation and washed with de-ionized water for three times, and finally dried in a freeze dryer. The effects of molar ratios of Eu/Gd and calcining temperature on the properties of RE-HAP nanocrystals such as phase composition, crystal size and luminescence was investigated. Moreover, the hemolysis and cytotoxicity of RE-HAP nanocrystals were evaluated respectively. The application of RE-HAP fluorescent nanocrystal for cell labeling was carried out. The location, luminescent signal and amount of intracellular RE-HAP nanocrystals were determined by TEM, LSCM and ICP. Results and Discussion: The crystalline phase of as prepared HAP:Eu/Gd samples showed a characteristic hexagonal structure of HAP crystal. The obtained HAP:Eu/Gd nanocrystalline was plate-like nanocrystal with a small size about 30-60nm. Comparing to Eu single-doped HAP, the fluorescence intensity of Eu/Gd coped HAP was enhanced. The further annealing could improve the luminescence intensity. Eu/Gd co-doped HAP nanocrystalline showed good blood compatibility and no cytotoxicity to L02 normal cells. After cultivated with HePG2 cancer cells, strong luminescence signal could be observed under fluorescence microscope. Conclusion: This study demonstrated that the luminescence enhanced RE-HAP nanocrystals could be obtained based on the synergistic effect of different rare earth elements co-doping. REs co-doped HAP nanocrystales should be more promising cell labels. Keywords: nanoparticle, Calcium phosphate, biomedical application, theranostic Conference: 10th World Biomaterials Congress, Montréal, Canada, 17 May - 22 May, 2016. Presentation Type: Poster Topic: Imaging with biomaterials Citation: Han Y, Xie Y, Perera T, Li F, Wang X and Li S (2016). Preparation of Eu3+/Gd3+ co-doped hydroxyapatite luminescent nanocrystals for cell labelling. Front. Bioeng. Biotechnol. Conference Abstract: 10th World Biomaterials Congress. doi: 10.3389/conf.FBIOE.2016.01.01393 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 27 Mar 2016; Published Online: 30 Mar 2016. Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Yingchao Han Yunfei Xie Tsh Perera Fang Li Xinyu Wang Shipu Li Google Yingchao Han Yunfei Xie Tsh Perera Fang Li Xinyu Wang Shipu Li Google Scholar Yingchao Han Yunfei Xie Tsh Perera Fang Li Xinyu Wang Shipu Li PubMed Yingchao Han Yunfei Xie Tsh Perera Fang Li Xinyu Wang Shipu Li Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.