Development of Cadmium-free and Multicolor Quantum Dots as Lifetime Imaging Probe

描述（由申请人提供）：由于半导体纳米晶体[量子点（QDs）]已被采用为一类新的荧光标记，许多研究表明，将量子点作为新的探针在体内和体外成像中具有广泛的潜在应用。与有机荧光团（1-5 ns）相比，量子点的寿命长（10s of ns），可以作为新的荧光寿命成像探针来降低细胞和组织的自身荧光背景（2-4 ns）。NIH SBIR项目将专注于开发新一代无镉、水溶性多色量子点，用于终身成像，以消除肿瘤细胞和组织切片中生物标志物的体外量子点成像的自身荧光。这种新方法的一个关键特点是通过在量子点核心中掺杂第三种元素而不是改变粒子尺寸来调整量子点发射颜色。由于这种新型掺杂量子点本身具有较长的发射寿命，并且量子点作为给体和掺杂离子作为受体可能具有较高的发射效率，因此在荧光标记的应用中引起了广泛的兴趣。掺杂的核/壳量子点将转化为水溶性和生物相容性，在实时成像领域具有潜在的生物医学应用前景。

DESCRIPTION (provided by applicant): Since semiconductor nanocrystals [quantum dots (QDs)] have been adopted as a new class of fluorescent labels, many studies have indicated a broad range of potential applications using QDs as new probes in vivo and in vitro imaging. Because of QDs long lifetimes (10s of ns) compared to organic fluorophores (1-5 ns), QDs can be used as new fluorescence lifetime imaging probes to reduce cells and tissue's autofluorescence background (2-4 ns). This NIH SBIR project will focus on developing a new generation of cadmium-free, water-soluble multicolor QDs for lifetime imaging to eliminate the autofluorescence for in vitro QD-imaging of biomarkers in tumor cells and tissue sections. A key feature of this new approach is to tune QD emission color by doping the QD core with a third element rather than changing the particle sizes. This kind of new type doped QDs should bring wide interest in the applications of fluorescence labeling due to long lifetime emissions from doped ion itself and possible high emission efficiency by QDs as donors and doped ions as accepters. The doped core/shell QDs would be converted to water soluble and biocompatible for the potential biomedical applications in the field of real-time imaging.