摘要：Theranostic nanoprobes can potentially integrate imaging and therapeutic capabilities into a single platform,offering a new personalized cancer diagnostic ***,there is a growing concern that their clinical application is not safe,particularly due to metal-containing elements,such as the gadolinium used in magnetic resonance imaging(MRI).We demonstrate for the first time that the photothermal melting of the dna duplex helix was a reliable and versatile strategy that enables the on-demand degradation of the gadolinium-containing MRI reporter gene from polydopamine(PDA)-based theranostic *** combination of chemotherapy(doxorubicin)and photothermal therapy,which leads to the enhanced anti-tumor *** vivo MRI tracking reveals that renal filtration was able to rapidly clear the free gadolinium-containing MRI reporter from the mice *** results in a decrease in the long-term toxic effect of theranostic MRI *** findings may pave the way to address toxicity issues of the theranostic nanoprobes.