In-capillary probing QDs and HAT tag self-assembly and displacement using Förster resonance energy transfer

Jianhao Wang; Jinchen Li; Chencheng Zhang; Jie Fan; Li Yang; Yaqin Gu; Feifei Liu; Cheli Wang; Bingyu Dong; Lin Qiu; Pengju Jiang

doi:10.1002/elps.201500356

In-capillary probing QDs and HAT tag self-assembly and displacement using Förster resonance energy transfer

Electrophoresis. 2015 Nov;36(21-22):2636-2641. doi: 10.1002/elps.201500356. Epub 2015 Oct 13.

Authors

Jianhao Wang¹, Jinchen Li¹, Chencheng Zhang¹, Jie Fan¹, Li Yang¹, Yaqin Gu¹, Feifei Liu¹, Cheli Wang¹, Bingyu Dong¹, Lin Qiu¹, Pengju Jiang¹

Affiliation

¹ School of Pharmaceutical Engineering and Life Science, Changzhou University, Changzhou, Jiangsu, P. R. China.

PMID: 26461971
DOI: 10.1002/elps.201500356

Abstract

HAT tag, a natural His affinity tag, is one of the most popular fusion tags. However, HAT tag containing three positive charges limited its self-assembly with quantum dots (QDs). Herein, ATTO 590-labeled HAT peptide was synthesized to self-assemble with QDs inside the capillary. QDs and ATTO 590-labeled HAT peptide were sequentially injected into the capillary and probed by fluorescence-coupled CE (CE-FL), showing an obvious Förster resonance energy transfer signal. Online self-assembly, separation, and detection were achieved within 10 min. CE-FL further revealed that imidazole and H₆ G₆ peptide could partially outcompete with HAT tag on the QDs surface inside the capillary. The displacement intermediates were separated clearly using CE-FL. Our study demonstrates the power of online CE-FL in analyzing the binding interaction between ligands containing positive charges and QDs.

Keywords: Fluorescence-coupled CE; Förster resonance energy transfer; Natural His affinity tag; Quantum dots; Self-assembly.