Study of the efficiency of chemiluminescence resonance energy transfer system based on hemin/G-quadruplex DNAzyme catalysis by chemiluminescence imaging

For designing and constructing a highly efficient CRET system, it is extremely important to systematically study the effects of reactants and the catalysts on the efficiency. In this paper, we investigated the effects of reactants and the catalyst hemin/G-quadruplex DNAzyme concentration, donor-acceptor ratio and distance on the CRET efficiency by CL imaging. The CRET system was based on hemin/G-quadruplex DNAzyme catalyzed luminol analogue L012 and hydrogen peroxide CL system, taking luminol analogue L012 as the energy donor and a quenching dye DABCYL labelled on the catalyst hemin/G-quadruplex instead of the donor as the energy acceptor. Our study showed that the concentrations of the CL reactants had no significant effect on the efficiency, while the concentration of the catalyst hemin/G-quadruplex had a great effect on the CRET efficiency. When the ratio of the energy donor to the acceptor was as high as 250, the efficiency was only reduced by 5.1%, which was quite different from that of FRET. In addition, a DNA double-stranded structure was designed at the end of G-quadruplex to control the distance between the donor and the acceptor. When the acceptor DABCYL was separated by different linker lengths (1, 5, 10, 20, and 30 base pairs) from the catalyst and the donor L012 molecules, the corresponding CRET efficiencies were 86.0%, 75.1%, 25.7%, 14.0%, and 5.0%, respectively. CL imaging was successfully used to study the efficiency of CRET with high throughput, low sample consumption, and high sensitivity. Our strategy would be beneficial to design and construct a highly efficient CRET system, enabling the interdisciplinary applications of CRET.

Automated summary

This paper systematically investigates the effects of reactants and catalysts on the efficiency of CRET using CL imaging. The results show that the concentration of the catalyst hemin/G-quadruplex has a significant impact on the CRET efficiency, while the concentration of the CL reactants has no significant effect. Additionally, controlling the distance between the donor and acceptor using a DNA double-stranded structure reveals a decrease in CRET efficiency with increasing distance.