溶酶体靶向荧光碳点的制备及细胞成像应用  

Preparation of Lysosome-targeting Carbon Dots and Its Application in Cell Imaging

作　　者：范子燕 刘正杰 张瑞龙[1] 韩光梅 张忠平 FAN Zi-Yan;LIU Zheng-Jie;ZHANG Rui-Long;HAN Guang-Mei;ZHANG Zhong-Ping(Information Materials and Intelligent Sensing Laboratory of Anhui Province,Institutes of Physical Science and Information Technology,School of Chemistry and Chemical Engineering,Anhui University,Hefei 230601,China;Key Laboratory of Photovoltaic and Energy Conservation Materials,Institute of Solid State Physics,HFIPS,Chinese Academy of Sciences,Hefei 230031,China)

机构地区：[1]安徽大学化学化工学院,物质科学与信息技术研究院信息材料与智能感知安徽省实验室,合肥230601 [2]中国科学院固体物理研究所,光伏与节能材料重点实验室,合肥230031

出　　处：《分析化学》2021年第7期1208-1217,共10页Chinese Journal of Analytical Chemistry

基　　金：国家自然科学基金项目(Nos.22074001,21874137,21974001,21775001);中国科学院科技服务网络计划项目(No.KFJ-STS-ZDTP-080)资助。

摘　　要：通过简单的一步功能化修饰制备了具有溶酶体靶向功能的发射蓝色荧光的水溶性荧光碳点,并成功用于活细胞内溶酶体的长时程成像。利用浓HNO_(3)氧化剥离炭黑得到富含羧基碳点,采用酰胺化反应,将N,N-二甲基乙二胺(N,N-Dimethylethylenediamine,DMEDA)修饰到碳点上,得到了DMEDA功能化的纳米荧光碳点(M-CDs)。红外光谱表征显示,与原始的羧基碳点相比,M-CDs在1658 cm^(-1)处出现了酰胺键(O=C-NH-)的特征振动峰,表明DMEDA成功修饰到碳点上。DMEDA的引入显著提高了碳点的荧光发射效率,量子产率达到15.6%,比修饰之前提高了约27倍,满足了细胞成像需求。M-CDs通过温度依赖的内吞方式进入细胞,与商业化染料Lyso-Tracker red的共定位实验表明,M-CDs定位在溶酶体内,并且是一种通用的溶酶体定位探针。与商业化染料Lyso Traker blue相比,M-CDs具有更强的光稳定性,在激光共聚焦显微镜下进行时间成像,设置扫描间隔为5 min,在长达120 min时间内对细胞进行25次激光扫描成像后,溶酶体内仍能检测到很强的蓝色荧光,表明M-CDs可以用于溶酶体的长时程成像。The lysosome-targeting carbon dots with excellent water solubility and strong blue emission were synthesized through a one-step functional modification for long-term lysosome imaging in living cells.Based on the carboxyl rich carbon dots synthesized by oxidizing carbon black in refluxing HNO_(3),N,N-dimethylethylenediamine(DMEDA)was chemically linked onto the carboxyl rich carbon dots through acylation reaction to obtain DMEDA modified carbon dots(M-CDs).The infrared spectrum of M-CDs showed the characteristic peak of acylamide(O=C-NH-)at 1658 cm^(-1),indicating the successful modification of DMEDA.The quantum yield of M-CDs was 15.6%,which was about 27 times higher than the original carboxyl rich carbon dots,meeting the requirement of cell imaging.The probe entered cells through temperature-dependent endocytosis way and the co-localization experiment with commercial dye Lyso-Tracker red showed that the probe localized in lysosomes and could be used as a universal lysosome tracker in different cell lines.Moreover,compared to commercially available Lyso-Tracker blue,M-CDs were more photostable under UV light.The fluorescence of M-CDs was still brightness after time-lapsed imaging by confocal microscopy for 120 min with an interval of 5 min in living cells,implying that the M-CDs could be used for long-te rm imaging of lysosomes.

关 键 词：碳点 功能化修饰 N N-二甲基乙二胺 溶酶体靶向 细胞成像 

分 类 号：Q2-33[生物学—细胞生物学] O657.3[理学—分析化学]