Magnetically controlled anisotropic light emission of DNA-functionalized supraparticles

Abstract

In this article, we show the DNA-functionalization of supraparticles, form their network, and manipulate the optical features of these networks by applying a magnetic field. We start with preparing the supraparticles (SPs) of semiconducting InP/ZnSeS/ZnS quantum dots (QDs), plasmonic silver nanoparticles, and superparamagnetic iron oxide nanoparticles. These SPs are prepared by employing azide-functionalized amphiphilic diblock or triblock copolymers as well as by using their combinations. Subsequently, we attached single-stranded DNAs to these SPs by employing copper-free click chemistry. Next, we hybridized DNA-coated QD SPs with the iron oxide SPs and formed a network. By applying a magnetic field, we restructured this network such that the iron oxide SPs are aligned. This led to an anisotropic emission from the QD SPs with a polarization ratio of 1.9. This study presents a proof-of-concept scheme to control the optical features of a self-assembled supraparticle system using an external interaction. We believe that our work will further contribute to the utilization of smart self-assembly techniques in optics and photonics.