Vicente Glorimar, Colón Luis A
Department of Chemistry, Natural Science Complex, University at Buffalo, The State University of New York, Buffalo, New York 14260-3000, USA.
Anal Chem. 2008 Mar 15;80(6):1988-94. doi: 10.1021/ac702062u. Epub 2008 Feb 16.
Capillary electrophoresis (CE) with laser-induced fluorescence (LIF) detection was used to separate different bioconjugated CdSe/ZnS quantum dots (QDs). The QD nanocrystals studied were conjugated to the biomolecules streptavidin, biotin, and immunoglobulin G. The bioconjugated QDs showed different electrophoretic mobilities, which appear to depend upon the biomolecule that is attached to the QD and the buffer solution used. The use of a polymeric additive into the CE run buffer improved the resolution of the bioconjugates. Under CE conditions, the interaction between QD bioconjugates containing streptavidin (QDSt) and biotin (QDBi) was monitored. Under a given set of experimental conditions, the fluorescence intensity of QDSt and QDBi emitting light at 655 nm indicated that about 90% of QDBi complexed with 70% of QDSt. A two-color experiment that made use of two different sizes of QD (i.e., 585 and 655 nm) indicated that 30% of the 655 nm QDBi complexed with 53% of the 585 nm QDSt. The use of QDs with different emission properties allows the selective monitoring of two different wavelengths while using one single excitation source. This, in turn, allowed the monitoring of overlapping peaks in the electropherogram when newly formed products resulting from the interaction of the two bioconjugated QDs appeared.
采用激光诱导荧光（LIF）检测的毛细管电泳（CE）技术分离不同的生物共轭CdSe/ZnS量子点（QD）。所研究的量子点纳米晶体与生物分子链霉亲和素、生物素和免疫球蛋白G共轭。生物共轭量子点表现出不同的电泳迁移率，这似乎取决于连接在量子点上的生物分子以及所使用的缓冲溶液。在CE运行缓冲液中加入聚合物添加剂提高了生物共轭物的分离度。在CE条件下，监测了含链霉亲和素的量子点生物共轭物（QDSt）和生物素的量子点生物共轭物（QDBi）之间的相互作用。在给定的一组实验条件下，QDSt和QDBi在655 nm处发射光的荧光强度表明，约90%的QDBi与70%的QDSt复合。利用两种不同尺寸的量子点（即585和655 nm）进行的双色实验表明，655 nm的QDBi中有30%与585 nm的QDSt中的53%复合。使用具有不同发射特性的量子点允许在使用单个激发源的同时选择性监测两个不同的波长。反过来，当由两种生物共轭量子点相互作用产生的新形成产物出现时，这允许监测电泳图中的重叠峰。
