Functional-Protein-Assisted Fabrication of Fe–Gallic Acid Coordination Polymer Nanonetworks for Localized Photothermal Therapy

Fe–polyphenols coordination polymers have emerged as a versatile theranostic nanoplatform for biological applications owing to the appealing biocompatibility of precursors from nature. Incorporating bioactive molecules with Fe–polyphenols coordination polymers is greatly significant to take full advantages of their superiorities for advanced application. Herein, we show functional-protein-assisted fabrication of Fe–gallic acid (GA) nanonetworks via a mild and facile biomineralization for photothermal therapy. Mild alkaline condition is crucial to obtain protein–Fe–GA nanonetworks with intense near-infrared absorption and their unique network structure allows reducing the leakage to the surrounding normal tissues, benefiting high photothermal therapeutic efficacy and minimal side effects. The proposed bovine serum albumin–Fe–GA nanonetworks are successfully used to eradicate tumor in vivo. In addition, this universal method can be extended to synthesize other protein-involved nanonetworks, such as human serum albumin–Fe–GA and ovalbumin–Fe–GA. More importantly, the intrinsic bioactivity of protein can be retained in the nanonetworks, and the ovalbumin–Fe–GA nanonetworks enable inducing the maturation of immune cells, showing the successful fusion of immune activity of ovalbumin into the nanonetworks. The proposed biomineralization strategy shows a bright prospect in incorporating various functional proteins, such as enzymes and antibodies, to form protein–Fe–GA nanonetworks with good biocompatibility, favorable photothermal effect, and specific biological function.