Bioactive MOFs Based Theranostic Agent for Highly Effective Combination of Multimodal Imaging and Chemo-Phototherapy.

Bioactive metal-organic frameworks (bio-MOFs) built from biofunctional metal ions and linkers show a new strategy to construct multifunctional theranostic platforms. Herein, a bio-MOF is synthetized via the self-assembling of Fe3+ ions and doxorubicin hydrochloride (DOX) molecules. Then, through a stepwise assembly strategy, another bio-MOFs structure consisting of Gd3+ ions and 1,3,5-benzenetricarboxylic acid (H3 BTC) is wrapped on the surfaces of Fe-DOX nanoparticles, followed by adsorbing photosensitizer indocyanine green (ICG). Specifically, the Gd-MOF shell structure can not only act as a contrast agent for magnetic resonance imaging (MRI), but also provides protection for Fe-DOX cores, controlling the release of DOX. The photoacoustic and photothermal imaging (PAI and PTI) methods are successfully introduced to the platform by loading ICG, providing potential applications for multimodal biological imaging. The in vitro and in vivo outcomes indicate that the Fe-DOX@Gd-MOF-ICG nanoplatform exhibits outstanding synergistic antitumor performance via MR/PA/PT imaging guided chemotherapy, photothermal and photodynamic combination therapy. The work may encourage further exploration of bio-MOFs based multifunctional theranostic platforms for multimodal imaging guided compound antitumor therapy, which will open an avenue of MOFs toward biological applications.

A one-pot synthesis of multifunctional Bi2S3 nanoparticles and the construction of core-shell Bi2S3@Ce6-CeO2 nanocomposites for NIR-triggered phototherapy.

As a direct thin band gap n-type semiconductor, bismuth sulfide (Bi2S3) nanomaterials possess great near-infrared (NIR)-triggered photothermal effects, photoacoustic (PA) and computed tomography (CT) imaging properties. Hence, Bi2S3 nanomaterials have become a research focal point in multiple domains, such as the construction of NIR-triggered nanosystems for cancer therapy. In this study, through a simple one-pot synthesis with the assistance of EDTA-2Na, we first obtained monodispersed spherical Bi2S3 of uniform particle sizes with fascinating photothermal and PA/CT imaging properties. Based on this, we introduced the photosensitizer Ce6 with photodynamic property and CeO2 with the O2-evolving characteristic, and thus designed a core-shell structure of the Bi2S3@Ce6-CeO2 nanocomposites (Bi2S3@Ce6-CeO2 NCs). The as-received Bi2S3@Ce6-CeO2 NCs exhibited a remarkable synergetic photothermal and photodynamic therapeutic effect both in vitro and in vivo, demonstrating its promising potential for cancer treatments. In the long term, the multifunctional PA/CT properties of both Bi2S3 NPs and Bi2S3@Ce6-CeO2 NCs in this study also supply a novel Bi2S3-based platform for constructing integrated diagnosis and treatment platforms.

Novel Tumor-Microenvironment-Based Sequential Catalytic Therapy by Fe(II)-Engineered Polydopamine Nanoparticles.

Traditional tumor treatments suffer from severe side effects on account of their invasive process and inefficient outcomes. Featuring a unique physical microenvironment, the tumor microenvironment (TME) provides a new research direction for designing more efficient and safer treatment paradigms. In this study, we fabricated a polydopamine (PDA)-based TME-responsive nanosystem, which successfully integrates glucose degradation, the Fenton reaction, and photothermal therapy for efficient cancer therapy. Through a convenient hydrothermal method, Fe2+-doped Fe(II)-PDA nanoparticles were successfully fabricated, which show an excellent photothermal effect and interesting reactivity for the Fenton reaction. Instead of introducing toxic anticancer agents, natural glucose oxidase (GOD) was grafted on Fe(II)-PDA, forming a cascade catalytic nanomedicine for a specific response to the glucose in TME. GOD grafted on Fe(II)-PDA-GOD is ought to catalyze abundant glucose in TME into gluconic acid and H2O2. The concomitant generation of H2O2 can enhance the efficiency of the sequential Fenton reaction, producing abundant hydroxyl radicals (•OH) for cancer therapy. Besides, the overconsumption of intratumoral glucose also could inhibit tumor growth by reducing the energy supply. Taken together, the in vitro and in vivo antitumor studies of such TME-based Fe(II)-PDA-GOD nanosystems displayed a favorable synergistic potency of glucose degradation, the Fenton reaction, and photothermal therapy against tumor growth. Our design expands the biological application of multifunctional PDA while providing novel strategies toward effective antitumor treatment with minimal side effects.