Nehilla Barrett J, Vu Tania Q, Desai Tejal A
Department of Biomedical Engineering, Whitaker Labs Room 701, Boston University, 44 Cummington Street, Boston, MA 02215, USA.
J Phys Chem B. 2005 Nov 10;109(44):20724-30. doi: 10.1021/jp052613+.
The unique advantages of quantum dot (QD) bioconjugates have motivated their application in biological assays. However, physical characterization of bioconjugated QDs after surface modification has often been overlooked. Here, biotinylated antibodies (biotin-IgG) were attached to commercial streptavidin-conjugated quantum dots (strep-QDs) at different stoichiometric ratios, and these QD bioconjugates were characterized with atomic force microscopy and discontinuous sodium dodecyl sulfate agarose gel electrophoresis (SDS-AGE). The results from these complementary analytical techniques showed that the molar ratio determined the relative sizes, molecular weights and morphologies of the QD bioconjugates. Additionally, the novel discontinuous SDS-AGE analysis confirmed specific binding between biotin-IgG and strep-QDs. Researchers who design QD bioconjugates for cell-based assays should consider stoichiometry-dependent differences in the physical properties of their QD bioconjugates.
量子点（QD）生物共轭物的独特优势推动了它们在生物检测中的应用。然而，表面修饰后生物共轭量子点的物理表征常常被忽视。在这里，生物素化抗体（生物素-IgG）以不同的化学计量比连接到商业链霉亲和素共轭量子点（链霉-QDs）上，并且这些量子点生物共轭物通过原子力显微镜和不连续十二烷基硫酸钠琼脂糖凝胶电泳（SDS-AGE）进行表征。这些互补分析技术的结果表明，摩尔比决定了量子点生物共轭物的相对大小、分子量和形态。此外，新型不连续SDS-AGE分析证实了生物素-IgG与链霉-QDs之间的特异性结合。为基于细胞的检测设计量子点生物共轭物的研究人员应考虑其量子点生物共轭物物理性质中依赖化学计量的差异。
