Lei Xialian, Li Renfu, Tu Datao, Shang Xiaoying, Liu Yan, You Wenwu, Sun Caixia, Zhang Fan, Chen Xueyuan
CAS Key Laboratory of Design and Assembly of Functional Nanostructures , Fujian Key Laboratory of Nanomaterials , Fujian Institute of Research on the Structure of Matter , Chinese Academy of Sciences , Fuzhou , Fujian 350002 , China . Email:
College of Materials Science and Engineering , Fujian Normal University , Fuzhou , Fujian 350007 , China.
Chem Sci. 2018 May 1;9(20):4682-4688. doi: 10.1039/c8sc00927a. eCollection 2018 May 28.
Near-infrared (NIR) II luminescence between 1000 and 1700 nm has attracted reviving interest for biosensing due to its unique advantages such as deep-tissue penetration and high spatial resolution. Traditional NIR-II probes such as organic fluorophores usually suffer from poor photostability and potential long-term toxicity. Herein, we report the controlled synthesis of monodisperse NaCeF:Er/Yb nanocrystals (NCs) that exhibit intense NIR-II emission upon excitation at 980 nm. Ce in the host lattice was found to enhance the luminescence of Er at 1530 nm with a maximum NIR-II quantum yield of 32.8%, which is the highest among Er-activated nanoprobes. Particularly, by utilizing the intense NIR-II emission of NaCeF:Er/Yb NCs, we demonstrated their application as sensitive homogeneous bioprobes to detect uric acid with the limit of detection down to 25.6 nM. Furthermore, the probe was detectable in tissues at depths of up to 10 mm, which enabled imaging of mouse organs and hindlimbs with high resolution, thus revealing the great potential of these NaCeF:Er/Yb nanoprobes in deep-tissue diagnosis.
1000至1700纳米之间的近红外（NIR）II发光因其具有诸如深层组织穿透和高空间分辨率等独特优势，已在生物传感领域引起了新的关注。传统的近红外II探针，如有机荧光团，通常存在光稳定性差和潜在的长期毒性问题。在此，我们报道了单分散NaCeF:Er/Yb纳米晶体（NCs）的可控合成，该纳米晶体在980纳米激发下表现出强烈的近红外II发射。发现主体晶格中的Ce增强了Er在1530纳米处的发光，最大近红外II量子产率为32.8%，这是Er激活的纳米探针中最高的。特别地，通过利用NaCeF:Er/Yb NCs的强烈近红外II发射，我们展示了它们作为灵敏的均相生物探针用于检测尿酸的应用，检测限低至25.6 nM。此外，该探针在深度达10毫米的组织中可检测到，这使得能够对小鼠器官和后肢进行高分辨率成像，从而揭示了这些NaCeF:Er/Yb纳米探针在深层组织诊断中的巨大潜力。
