Block Copolymer‐Stabilized Metal–Organic Framework Hybrids Loading Pd Nanoparticles Enable Tumor Remission Through Near‐Infrared Photothermal Therapy

Abstract

Metal–organic frameworks (MOFs), such as the magnetic resonance imaging‐fit MIL‐100 based on Fe, are gaining significant attention as versatile theranostics with high‐loading capability. Moreover, as MOFs can be engineered to target tumors, there is much interest in applying them for precise pin‐point treatment of cancer. Herein, Pd nanoparticles within MIL‐100(Fe) are generated to create MOFs with remarkable photothermal conversion properties for cancer therapy. The Pd‐loaded MIL‐100(Fe) (Pd@MIL‐100(Fe)) are stabilized with biocompatible block copolymers to generate MOFs with PEGylated surfaces. This is achieved by directly mixing poly(ethylene glycol)‐poly(L‐aspartic acid) (PEG‐p(Asp)) or dopamine‐modified PEG‐p(Asp) (PEG‐p(Asp‐Dopa)) block copolymers with the MOFs in aqueous conditions. The resulting block copolymer‐stabilized MOF hybrids are stable in physiological conditions. Particularly, the Pd@MIL‐100(Fe)/PEG‐p(Asp‐Dopa) hybrids show enhanced blood circulation and increased accumulation in B16F10 melanoma. Furthermore, when irradiated with 808 nm light, the Pd@MIL‐100(Fe)/PEG‐p(Asp‐Dopa) hybrids rapidly increase the temperature to 50 °C, enabling tumor remission. The surface‐stabilized Pd@MIL‐100(Fe)/polymer hybrids open viable opportunities for innovating MOF/polymer hybrid‐based approaches for drug delivery.