L-Cys/MPA共修饰CdTe量子点:制备、表征及其在细胞标记中的应用  

CdTe Quantum Dots Using L-Cys/MPA as Mixed-ligands:Preparation,Characterization and Application in Cell Labeling

作　　者：丁兆强[1] 权静[1] 聂华丽[1] 朱利民[1] 

机构地区：[1]东华大学化学化工与生物工程学院,上海201620

出　　处：《影像科学与光化学》2015年第2期126-135,共10页Imaging Science and Photochemistry

基　　金：国家自然科学基金项目(21006010);中央高校基本科研业务经费专项资金资助

摘　　要：以L-半胱氨酸（L-Cys）和巯基丙酸（MPA）为共修饰剂在水相中快速合成高质量CdTe量子点。通过紫外-可见分光光谱、荧光光谱、荧光寿命衰减曲线、透射电子显微图片、XRD图谱等相关方法对产物进行表征。调节L-Cys和MPA的摩尔比,对CdTe量子点的生长速率和光学特性有明显影响。结果证实：与单一修饰剂L-Cys或MPA相比,L-Cys/MPA共修饰CdTe量子点具有较快的荧光发射峰红移速率,且其粒径分布均一、稳定性强。50L-CdTe（LCys与MPA摩尔比为50%）的荧光量子产率达到66.4%,75L-CdTe（L-Cys与MPA摩尔比为75%）的荧光寿命为46.8ns。细胞毒性实验证明75L-CdTe量子点对SiHa细胞毒性较小,细胞存活率为75%~95%。进一步将其用于标记细胞,表明75L-CdTe量子点能有效地对SiHa细胞进行荧光标记。L-Cys/MPA共修饰CdTe量子点具有良好的荧光特性和生物相容性,在生物医药领域具有重要的应用价值。High-quality CdTe quantum dots（QDs）were rapidly synthesized in aqueous phase using both LCysteine（L-Cys）and mercaptopropionic acid（MPA）as mixed-ligands.Different technologies including UV-Vis spectra,fluorescence spectra,luminescence decay curves,transmission electron microscopy and X-ray diffraction analysis were employed to characterize the prepared QDs.The ratio of L-Cys and MPA was found to have influence on the growth kinetics and optical properties of the obtained QDs.Compared to single ligand of L-Cys or MPA,L-Cys/MPA as mixed-ligands could accelerate the red shifted rate of fluorescence emission peak wavelength effectively.CdTe QDs capped with mixed-ligands exhibited a high uniformity in diameter and an excellent photostability.50L-CdTe（L-Cys/MPA molar ratio was 50%）held a high quantum yield of 66.4%and 75L-CdTe（L-Cys/MPA molar ratio was 75%）exhibited a luminescence decay lifetime of 46.8ns.MTT assays showed that 75L-CdTe with emission of 615 nm maintained 75%-95% SiHa cell viability.Further study of labeling SiHa cell with the as-prepared 75L-CdTe indicated that the QDs are excellent biomarkers for SiHa cell.L-Cys and MPA as mixed-ligands with proper design can be employed to fabricate CdTe QDs with superior fluorescence properties and biocompatibility,which have potential in biological and medical fields as biomarkercandidates.

关 键 词：细胞标记 量子点 共修饰 L-半胱氨酸 巯基丙酸 

分 类 号：O657.3[理学—分析化学]