Facile Synthesis of Basic Copper Carbonate Nanosheets for Photoacoustic Imaging-Guided Tumor Apoptosis and Ferroptosis and the Extension Exploration of the Synthesis Method.

Elimination of tumor cells using carbonate nanomaterials with tumor microenvironment-responsive capacity has been explored as an effective strategy. However, their therapeutic outcomes are always compromised by the relatively low intratumoral accumulation and limited synthesis method. Herein, a novel kind of basic copper carbonate nanosheets was designed and prepared using a green synthesis method for photoacoustic imaging-guided tumor apoptosis and ferroptosis therapy. These nanosheets were synthesized with the assistance of dopamine and ammonium bicarbonate (NH 4 HCO 3 ) and the loading of glucose oxidase (GOx). NH 4 HCO 3 could not only provide an alkaline environment for the polymerization of dopamine but also supply carbonates for the growth of nanosheets. The formed nanosheets displayed good acid and near-infrared light responsiveness. After intercellular uptake, they could be degraded to release Cu 2+ and GOx, generating hydroxyl radicals through a Cu + -mediated Fenton-like reaction, consuming glucose, up-regulating H 2 O 2 levels, and down-regulating GSH levels. Tumor elimination could be achieved by hydroxyl radical-induced apoptosis and ferroptosis. More amusingly, this synthesis method can be extended to several kinds of mono-element and multi-element carbonate nanomaterials (e.g., Fe, Mn, and Co), showing great potential for further tumor theranostics.