中文摘要：

目的制备半导体量子点-Smad2单克隆抗体荧光探针（QDs-Smad2单抗荧光探针）,并对其相关光学性质和特异免疫性识别能力进行检测。方法1）用半导体量子点和Smad2单克隆抗体通过化学偶联法制备水溶性的QDs-Smad2单抗荧光探针并纯化;2）用紫外分光光度计和荧光分光光度计分别测定QDs-Smad2单抗荧光探针的吸收光谱、发射光谱,在激光共聚焦显微镜下观察并检测QDs-Smad2单抗荧光探针的形态、荧光强度和光化学稳定性;3）转化生长因子-β1（TGF-β1）和大鼠牙乳头细胞共同孵育24h后,采用SP免疫细胞化学法和QDs-Smad2单抗荧光探针直接免疫荧光成像法观察比较Smad2信号蛋白分子在大鼠牙乳头细胞内的分布,并检测细胞内QDs-Smad2单抗荧光探针的相关光学性质。结果半导体量子点与Smad2单抗通过共价结合形成稳定的QDs-Smad2单抗荧光探针,QDs-Smad2单抗荧光探针对大鼠牙乳头细胞内Smad2分子具有特异性的识别能力;QDs-Smad2单抗荧光探针仍具有QDs所具有的激发光谱宽,发射光谱窄,荧光度强,光化学稳定性好等优良光学特征。结论生物修饰的半导体量子点和单克隆抗体通过共价结合形成纳米分子探针后仍具有特异免疫识别能力和量子点独特的光学性质,这为半导体量子点用于活细胞内对蛋白质分子进行实时、原位、长时间动态可视化检测提供了科学基础和依据。

英文摘要：

Objective To prepare semiconductor quantum dots（QDs）-Smad2 monoclonal antibody fluorescent probes, to detect the optical qualities and the ability to specific recognition of Smad2 in rat dental papillae cells （RDPC） of quantum dots-Smad2 monoclonal antibody fluorescent probes. Methods 1）QDs were chemically modified with Smad2 proteins to prepare water soluble QDs-Smad2 monoclonal antibody fluorescent probes which were purified after pre- paratiorr 2）The absorption band and emission band of these probes were obtained through ultraviolet spectrophotometer and fluorospectrophotometer, the .shape, fluorescence intensity and photochemistry stability of these probes were studied through confocal laser scanning fluorescence microscopy. 3）Before the location of Smad2 proteins in RDPC was studied with anti-Smad2 immunocytochemical method and direct immunofluorescence imaging, RDPC were incubated with transforming growth factor-β1 （TGF-β1）, and the related optical qualities of quantum dots-Smad2 monoclonal antibody fluorescent probes in RDPC were detected. Results QDs and monoclonal antibody linked together through covalent bond to form the fluorescent probes which could specifically and effectively recognize Smad2 proteins in RDPC. These fluorescent probes still had good properties, including broad excite spectra, narrow emission spectra, high fluorescence intensity and photostability. Conclusion QDs and monoclonal antibody could link together through covalent bond to form the nanometer molecular probes with distinct optics character and photostability, which provides the scientific evidence that QDs can visualize the molecular movement in living cells in long-term, in situ and in real time.