Preparation and Characterization of DNA-assembled GRS-DNA-CuS Nanodandelions

In this study, we introduce a detailed protocol for the preparation of DNA-assembled GRS-DNA-copper sulfide (CuS) nanodandelion, a multifunctional theranostics nanoparticle. Using transmission electron microscope (TEM) and dynamic light scattering techniques, we characterize the physicochemical property of DNA-assembled GRS-DNA-CuS nanodandelions and their dissociation property after the first near-infrared (NIR) light irradiation. In addition, we systematically monitor the processes of tumor accumulation and uniform intratumoral distribution (UITD) of ultrasmall CuS photothermal agents (PAs), which are dissociated from GRS-DNA-CuS nanodandelions, by Raman imaging and photoacoustic imaging, respectively. The UITD of the dissociated ultrasmall CuS PAs can enhance the therapeutic efficiency of photothermal treatment under the second NIR light irradiation. Overall, this protocol provides a powerful tool to achieve UITD of PAs by explosively breaking the hydrogen bonds of DNA in GRS-DNA-CuS nanodandelions under NIR light irradiation. We expect DNA-assembled nanotheranostics to serve as a robust platform for a variety of biomedical applications related to photothermal therapy in the oncology field. This protocol can increase experimental reproducibility and contribute to efficient theranostics nanomedicine.