Rational synthesis of three-dimensional core-double shell upconversion nanodendrites with ultrabright luminescence for bioimaging application

Murad M A Abualrejal; Kamel Eid; Rongrong Tian; Lin Liu; Hongda Chen; Aboubakr M Abdullah; Zhenxin Wang

doi:10.1039/c9sc01586h

Rational synthesis of three-dimensional core-double shell upconversion nanodendrites with ultrabright luminescence for bioimaging application

Chem Sci. 2019 Jun 19;10(32):7591-7599. doi: 10.1039/c9sc01586h. eCollection 2019 Aug 28.

Authors

Murad M A Abualrejal^{1

2}, Kamel Eid³, Rongrong Tian^{1

2}, Lin Liu^{1

4}, Hongda Chen¹, Aboubakr M Abdullah³, Zhenxin Wang^{1

2}

Affiliations

¹ State Key Laboratory of Electroanalytical Chemistry , Changchun Institute of Applied Chemistry , Chinese Academy of Sciences , Changchun , 130022 , P. R. China . Email: wangzx@ciac.ac.cn.
² University of Science and Technology of China , Road Baohe District , Hefei , Anhui 230026 , P. R. China.
³ Centre for Advanced Materials , Qatar University , Doha 2713 , Qatar.
⁴ College of Chemistry , Jilin University , Changchun 130012 , P. R. China.

Abstract

Engineering the morphology of rare-earth doped NaYF₄-based upconversion nanoparticles (UCNPs) can effectively tune their upconversion luminescence emission (UCLE) properties. Herein, we rationally synthesized a new class of three-dimensional upconversion core-double-shell nanodendrites (UCNDs) including an active core (NaYF₄:Yb,Er,Ca) capped by a transition layer (NaYF₄:Yb,Ca) and an active outer shell (NaNdF₄:Yb,Ca). The high concentration of the Nd³⁺ sensitizer in the outer dendritic shell enhances the luminescence intensity, while the transition layer enriched with Yb³⁺ acts as an efficient energy migration network between the outer shell and inner core along with preventing the undesired quenching effects resulting from Nd³⁺. These unique structural and compositional merits enhanced the UCLE of UCNDs by 5 and 15 times relative to NaYF₄:Yb,Er,Ca@NaYF₄:Yb,Ca truncated core-shell UCNPs and NaYF₄:Yb,Er,Ca spherical core UCNPs, respectively, under excitation at 980 nm. The SiO₂-COOH layer coated UCNDs (UCND@SiO₂-COOH) were successfully used as efficient long-term luminescent probes for in vitro and in vivo bioimaging without any significant toxicity. The uptake and retention of UCND@SiO₂-COOH were mostly found in the liver and spleen. This study may open the way towards the preparation of three-dimensional UCND nanostructures for biomedical applications.