PEG修饰的硅量子点应用于细胞的二次谐波成像  

Second Harmonic Imaging of PEG-Coated Silicon Quantum Dots in Cells

作　　者：陈蕾[1] 向进 赵年 陈同生 Chen Lei;Xiang Jin;Zhao Nian;Chen Tongsheng(College of Physics and Optoelectronic Engineering,Foshan University,Foshan 528000,Guangdong,China;Key Laboratory of Optoelectronic Technology and Systems(Ministry of Education),College of Optoelectronic Engineering,Chongqing University,Chongqing 400044,China;College of Physics and Optoelectronics,Xiangtan University,Xiangtan 411105,Hunan,China;Guangdong Key Laboratory of Laser Life Science,College of Biophotonics,South China Normal University,Guangzhou 510631,Guangdong,China)

机构地区：[1]佛山科学技术学院物理与光电工程学院,广东佛山528000 [2]重庆大学光电工程学院,光电技术及系统教育部重点实验室,重庆400044 [3]湘潭大学物理与光电工程学院,湖南湘潭411105 [4]华南师范大学生物光子学研究院,广东省激光生命科学重点实验室,广东广州510631

出　　处：《中国激光》2023年第21期115-122,共8页Chinese Journal of Lasers

基　　金：国家自然科学基金(62105062)。

摘　　要：二次谐波成像作为一种高空间分辨率和高穿透深度的非线性光学成像技术,可以避免荧光成像中由能量吸收导致的光漂白和饱和吸收等问题,在临床诊断和生物医学领域具有广阔的应用前景。笔者引入了一种具有中心反演对称破缺、高非线性光学效应的材料——硅量子点作为二次谐波探针,同时为了增强硅量子点的生物亲和性并减少其表面氧化,利用聚乙二醇对硅量子点进行修饰,并将其作为生物探针探究了其在人肝癌细胞(HepG2)中的二次谐波成像效果。通过与双光子荧光成像结果进行对比发现,基于聚乙二醇修饰的硅量子点的二次谐波成像技术具有可靠性和稳定性。本研究对未来硅量子点在分子成像、药物递送和干细胞治疗中的应用具有积极的推动作用。Objective As a nonlinear optical imaging technique that offers high spatial resolution and high penetration depth,second harmonic imaging holds great promise for clinical diagnosis and various applications in the biomedical field,because it overcomes photobleaching and saturation absorption owing to energy absorption,which are commonly encountered in fluorescence imaging.Second-harmonic generation(SHG)is a nonlinear optical process in which two identical photons interact with a nonlinear material and are effectively converted into a single photon with precisely twice the frequency of the incident beam.In biologically relevant SHG imaging,the predominant approach has traditionally relied on the use of exogenous dye markers or endogenous proteins with a relatively low SHG efficiency.In fact,numerous studies have demonstrated strong and photostable SHG signals generated by inorganic crystalline materials.However,most of these inorganic crystalline materials contain heavy metals and have relatively large sizes(~100 nm in diameter).Recently,silicon quantum dots(SiQDs)were developed and have attracted growing interest owing to their remarkable properties,such as aqueous solubility,low cytotoxicity,high quantum yield,and exceptional stability against photobleaching.However,only few studies have investigated the generation of SHG signals from SiQDs without structural reconstitution,which has great potential for advanced optical applications,particularly in the field of SHG imaging.In this study,we developed polyethylene glycol(PEG)-coated SiQDs,an asymmetric material with a high nonlinear optical effect,as second-harmonic probes.To enhance the biological affinity and reduce the surface oxidation of the SiQDs,we modified their surface with PEG and investigated the imaging effect of PEG-coated SiQDs as a biological probe for second-harmonic wave imaging in HepG2 cells.Compared to two-photon fluorescence imaging,the second-harmonic imaging technique based on PEG-coated SiQDs provides more reliable and stable results.This fi

关 键 词：非线性光学 二次谐波成像 硅量子点 人肝癌细胞 生物探针 

分 类 号：O734.1[理学—晶体学]