One-Pot Rapid Synthesis of Cu<sup>2+</sup>-Doped GOD@MOF to Amplify the Antitumor Efficacy of Chemodynamic Therapy
Qing Li, Jiantao Yu, Lin Li, Yulin Zhu, Zixiang Wei, Feiyan Wan, Xindan Zhang, Feng He, Leilei Tian
Abstract
Chemodynamic therapy (CDT) relies on the transformation of intracellular hydrogen peroxide (H 2 O 2 ) to hydroxyl radicals (·OH) with higher toxicity under the catalysis of Fenton/Fenton-like reagents, which amplifies the oxidative stress and induces significant cellular apoptosis. However, the CDT efficacy is generally limited by the overexpressed GSH and insufficient endogenous H 2 O 2 in tumors. Co-delivery of Cu 2+ and glucose oxidase (GOD) can lead to a Cu 2+ /Cu + circulation to realize GSH depletion and amplify the Fenton-like reaction. pH-responsive metal–organic frameworks (MOFs) are the optical choice to deliver Fenton/Fenton-like ions to tumors. However, considering that the aqueous condition is requisite for GOD encapsulation, it is challenging to abundantly dope Cu 2+ in ZIF-8 MOF nanoparticles in aqueous conditions due to the ease of precipitation and enlarged crystal size. In this work, a robust one-pot biomimetic mineralization method using excessive ligand precursors in aqueous conditions is developed to synthesize GOD@Cu-ZIF-8. Copper ions abundantly doped to the GOD@Cu-ZIF-8 can eliminate GSH to produce Cu +, which is further proceeded to the Fenton-like reaction in the presence of GOD-catalyzed H 2 O 2 . Through breaking the tumor microenvironment homeostasis and producing an enhanced CDT effect, the promising antitumor capability of GOD@Cu-ZIF-8 was evidenced by the experiments both in vitro and in vivo .