Single-molecule and Nanobiology Laboratory, Department of Biophysics, School of Basic Medical Sciences and Biomed-X Center, Peking University, Beijing, 100191, China.
Single-molecule and Nanobiology Laboratory, Department of Biophysics, School of Basic Medical Sciences and Biomed-X Center, Peking University, Beijing, 100191, China.
Colloids Surf B Biointerfaces. 2018 Dec 1;172:752-759. doi: 10.1016/j.colsurfb.2018.09.002. Epub 2018 Sep 5.
We here report a facile synthesis of chitosan shelled quantum dot (QD/fGC) that holds essential properties requisite for biological applications, such as excellent water solubility, super colloidal stability, and low nonspecific adsorption as well as ease of functionalization. In this method, the amphiphilic glycol chitosan fragment (MW 1.0-1.7 kDa) was assembled on the top of CdSeS/ZnS nanocrystal through hydrophobic interaction in aqueous solution, without displacing the native coordinating ligands, which result in a higher quantum yield of about 0.26, 46% of the uncoated CdSeS/ZnS QDs in chloroform (0.57). In addition, the prepared QD/fGC composes an individual semiconductor core and presents an extremely small size of about 6.03 ± 1.50 nm (n = 399) in diameter. By conjugation with bioactive amines via 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC)-based hydroxyl activation approach, the functionalized QD/fGC presented excellent recognition of specific cells in fluorescent imaging. Our work provides a new general method of chitosan modification of hydrophobic nanoparticles for biomedical applications.
我们在此报告了一种壳聚糖包覆量子点（QD/fGC）的简便合成方法，该方法具有许多生物应用所必需的特性，如优异的水溶性、超胶体稳定性、低非特异性吸附以及易于功能化。在该方法中，通过疏水相互作用，两亲性的乙二醇壳聚糖片段（MW 1.0-1.7 kDa）在水溶液中组装在 CdSeS/ZnS 纳米晶体的顶部，而不会取代原有的配位配体，这导致量子产率约为 0.26，而在氯仿中未包覆的 CdSeS/ZnS QD 的量子产率为 0.57（46%）。此外，所制备的 QD/fGC 由单个半导体核组成，其直径非常小，约为 6.03±1.50nm（n=399）。通过与生物活性胺通过 1-乙基-3-（3-二甲基氨基丙基）碳二亚胺（EDC）-基于羟基活化的方法偶联，功能化的 QD/fGC 在荧光成像中对特定细胞具有出色的识别能力。我们的工作为用于生物医学应用的疏水纳米颗粒的壳聚糖修饰提供了一种新的通用方法。
