In Situ Transformable Pro-nanotheranostic Platform for Activable Photoacoustic Imaging and Synergistic Photothermal/Chemodynamic Cancer Therapy

Abstract

Nanotheranostic platforms integrated with diagnostic and therapeutic functions have been widely developed for tumor medicine. However, the "always-on" nanotheranostic platforms suffer from poor tumor specificity, which may largely restrict therapeutic efficacy and prevent precise theranostics. Here, we develop an in situ transformable pro-nanotheranostic platform (ZnS/Cu 2 O@ZIF-8@PVP) by encapsulating ZnS and Cu 2 O nanoparticles in a metal−organic framework (MOF) nanomaterial of ZIF-8 that allows activable photoacoustic (PA) imaging and synergistic photothermal/chemodynamic therapy (PTT/CDT) of tumors in vivo. It is shown that the pro-nanotheranostic platform gradually decomposes and releases ZnS nanoparticles and Cu + ions in acidic conditions, which spontaneously trigger a cation exchange reaction and synthesize Cu 2 S nanodots in situ with activated PA signals and PTT effects. Moreover, the excessive Cu + ions function as Fenton-like catalysts and catalyze the production of highly reactive hydroxyl radicals ( • OH) for CDT using elevated levels of H 2 O 2 in tumor microenvironments (TMEs). In vivo studies demonstrate that the in situ transformable pro-nanotheranostic platform can specifically image tumors via PA and photothermal imaging and efficiently ablate tumors through synergistic CDT/PTT. Our in situ transformable pro-nanotheranostic platform could provide a new arsenal for precise theranostics in cancer therapy.

Ultrasound-Based Micro-/Nanosystems for Biomedical Applications

“…In 2023, Han et al constructed a ZnS/Cu 2 O@ZIF-8@PVP pre-nanotherapeutic platform for PA imaging and CDT . The gradual decomposition of the material in mildly acidic environments significantly enhanced the precision of the therapeutic approach.…”

Acid-Responsive Decomposable Nanomedicine Based on Zeolitic Imidazolate Frameworks for Near-Infrared Fluorescence Imaging/Chemotherapy Combined Tumor Theranostics

“…Among them, the solvothermal method is the most widely adopted approach to obtain ZIF-8 NPs and their composite NPs loaded with functional molecules in organic solvents or water [ 15 , 26 ]. Moreover, ZIF-8 NPs, serving as nanocarriers encapsulating functional molecules, are usually prepared via two-step or one-pot approaches [ 17 , 26 , 27 ]. Specifically, the former approach separates the construction of the ZIF-8 structure and the encapsulation of functional molecules as two distinct processes, whereas the latter strategy integrates the two processes synchronously, resulting in more abundant encapsulation of functional molecules [ 17 , 26 ].…”

Target Design of Multinary Metal–Organic Frameworks for Near-Infrared Imaging and Chemodynamic Therapy

“…Recently, composite materials with both CDT units (Fe/Cu/Mn ions and oxides, etc. ) − and imaging units (dye molecules, quantum dots, upconversion nanoparticles, polymers, etc. ) − ,− have been applied to achieve imaging-guided CDT.…”

“…) − ,− have been applied to achieve imaging-guided CDT. However, heterogeneous distribution of the units in the composites (sometimes with additional carriers) − makes deciphering the structure–efficacy relationship very difficult. Furthermore, the imaging and therapy may not be synchronized in time or act at the same site in biological environments due to their nonuniform and dissociative/disintegrative nature.…”