NIR‐II Light Accelerated Prodrug Reduction of Pt(IV)‐Incorporating Pseudo Semiconducting Polymers for Robust Degradation and Maximized Photothermal/Chemo‐Immunotherapy

Abstract

AbstractSelective activation of Pt(IV) prodrugs within tumors is particularly attractive because of their low damage to normal tissues. However, current common activation via chemical/photoreduction of Pt(IV) prodrugs into Pt(II) counterparts is limited by undesirable spatial–temporal control over this reduction process and the ineffective tissue penetration depth of undesirable light. Here, a pseudo‐conjugated‐polymer is designed via Stille polymerization, resulting in PSP‐Pt with a Pt(IV) prodrug of oxaliplatin (Oxa(IV)) in the polymer main chain that can be activated by NIR‐II light. PSP‐Pt can co‐assemble with a commercially available lipid polymer, namely mPEG2k‐DSPE, into NPPSP‐Pt. Under 1064 nm light irradiation, NPPSP‐Pt can be photoactivated to accelerate the Pt(IV) reduction to release oxaliplatin, thereby killing the cancer cells by photothermal effect and chemo‐immunotherapy inside a mouse model with CT26 colon cancer. This work reports the application of NIR‐II light for accelerating Pt(IV) reduction for cancer tumor therapy.