Water-Dispersed Near-Infrared-Emitting Quantum Dots of Ultrasmall Sizes for inVitro and in Vivo Imaging
Yao He*, Yiling Zhong, Yuanyuan Su, Yimei Lu, Ziyun Jiang, Fei Peng, Tingting Xu, Shao Su, Qing Huang, Chunhai Fan*, Shuit-Tong Lee*
Institute of Functional Nano & Soft Materials (FUNSOM) and Jiangsu Key Laboratory for Carbon-based Functional Materials & Devices, Soochow University, Suzhou 215123, China
NIR fluorescence imaging is widely recognized as an effective method for high-resolution and high-sensitivity bioimaging due to minimal biological autofluorescence background and increased penetration of excitation and emission light through tissue. In this report, we present a new class of water-dispersed NIR-emitting quantum dots (QDs) with ultrasmall sizes, which are directly prepared in aqueous phase via a facile one-step microwave synthesis for the first time. Significantly, the prepared NIR-emitting QDs possess excellent aqueous dispersibility, strong photoluminescence, robust storage-, chemical-, and photo-stability, and finely tunable emission in the NIR range (700-800 nm). The QDs are readily functionalized with antibodies for use in immunofluorescent bioimaging, yielding highly spectrally and spatially resolved emission for both in-vitro and in-vivo imaging. Distinctively, in comparison to the large size of 15-30 nm of the conventional NIR QDs, the extremely small size (~3.7 nm or 10.0 nm measured by TEM or DLS, respectively) of our QDs offers great opportunities for high-efficiency and high-sensitivity targeted imaging in cells and animals.
Editor: Danting Xiang