量子点标记壳聚糖衍生物自聚集纳米胶束的制备与表征  

Preparation and Characterization of Quantum Dots-tagged Self-assembly Nanoparticles

作　　者：杨永[1] 董晓庆[1] 张磊[1] 常津[1] 

机构地区：[1]天津大学材料科学与工程学院纳米生物技术研究所,天津300072

出　　处：《高分子通报》2007年第6期38-44,共7页Polymer Bulletin

基　　金：国家自然科学基金(50373033);天津市应用基础研究重点基金(No:05YFJZJC01001)

摘　　要：以EDC为偶联剂,将胆酸接枝到赖氨酸改性的壳聚糖主链的氨基上,得到一系列胆酸取代度相同(4.2%)而赖氨酸取代度不同(2.3%,4.4%,9.6%)的双亲性壳聚糖衍生物(CA-LysCS),利用FT-IR,1H NMR对其结构进行表征。CA-LysCS在水相中自组装形成自聚集体。以芘为荧光探针对其自聚集行为进行了研究,结果显示制得的自聚集体具有较之小分子表面活性剂较低的CAC(1.1×10-2～5.3×10-2mg/mL),表明自聚集体可在水相中形成稳定的胶束。且随着赖氨酸取代度的增加,CAC值随之增大。以激光粒度仪对自聚集体水相中的粒径分布进行了研究,发现其平均粒径随着赖氨酸取代度的增大有所增加(164.6～414.3nm)。以三辛基氧化膦(TOPO)为包裹剂,制备了油溶性硫化镉(CdSe)绿色量子点。用制备的自聚集体对量子点进行了包裹,TEM照片显示量子点位于自聚集体的疏水化核内。以荧光分光光度计对量子点的荧光特性进行了研究,发现包裹后量子点的荧光强度有所减弱。Various cholic acid modified lysine grafted chitosan（CA-LysCS） with the same degrees of substitute （DS） of cholic acid （4.2%） and different degrees of substitute （DS） of Lysine（2.3%,4.7%,9.3%） were synthesized with the EOC as the coupling reagent. Structural characteristics of these products were investigated using FT-IR and I HNMR. The critical aggregation concentration（CAC） of the self-aggregate of CA-LysCS were determined by measuring the fluorescence intensity of the pyrene as a fluorescent probe, which increased with increase of DS of Lysine in the range of 1.1 -5.3 × 10^-2 mg/mL. The average particle size of self-aggregates in distilled water also increased with the increase of the DS of Lysine in the range of 164.6- 414.3nm. These self-assembly nanoparticles were tagged using TOPO-capped green quantum dots （QDs）. A transmission electron microscopy study showed that the quantum dots located in the hydrophobic core of the micelles. The flurescence intensity of green Quantum dots decreased after encapsulated mainly due to the covering of the micelles.

关 键 词：壳聚糖 胆酸 赖氨酸 纳米粒子 自聚集 量子点(QDs) 胶束 

分 类 号：TB383.1[一般工业技术—材料科学与工程]