In-Situ Assembly of Self-Photosensitizing Crystalline Copper(I) Coordination Networks for Photocatalytic CO Reduction.

Crystalline coordination networks (CCNs) offer rigid and highly organized structures that stabilize metal ions in unique coordination geometries, oxidation states, and electronic configurations, enabling unexpected catalytic properties. In this study, we introduce two photocatalytic CCNs, CuTTC-E and CuTTC-M, synthesized from noncatalytic Cu-(I) ions and nonphotosensitizing trithiocyanuric acid (TTC) linkers, without reliance on precious metals or expensive photosensitizing ligands. Structural analysis revealed that CuTTC-E features [CuSCl] secondary building units (SBUs) that are catalytically active for CO reduction to CO.

Monolayered Metal-Organic Framework Unlocks Integration of Shaped Nanoparticles for Synergistic Photocatalysis.

Metal-organic frameworks (MOFs) with ordered structures and high surface areas are promising supports for metal nanoparticles (MNPs) in synergistic catalysis. However, their limited pore sizes restrict integration to small spherical MNPs, excluding shaped MNPs that are critical for exposing specific lattice surfaces and achieving a superior catalytic performance. In this work, we address this limitation by reducing MOFs to monolayers, enabling the integration of shaped MNPs onto their surfaces to significantly enhance the catalytic efficiency.

Dimensionality Reduction of Metal-Organic Frameworks to Monolayers for Enhanced Electrocatalysis.

Metal-organic frameworks (MOFs) are potential candidates for electrocatalysis due to their well-defined, tunable structures, and ability to incorporate diverse active sites. However, their inherent insulating nature restricts electron transfer from electrode to remote active sites, leading to diminished catalytic performance. In this work, we present a novel strategy to overcome this limitation by reducing 3D MOFs (3D_MOFs) into monolayered MOFs (monoMOFs) with a thickness of ∼1.

Hybrid biological-chemical strategy for converting polyethylene into a recyclable plastic monomer using engineered Corynebacterium glutamicum.

Converting polyethylene (PE) into valuable materials, particularly ones that are better for the environment than the incumbent plastics, not only helps mitigate environmental issues caused by plastic waste but also alleviates the long-standing problem of microbial fermentation competing with food supplies. However, the inherent robustness of PE due to its strong carbon-carbon bonds and high molecular weight necessitates harsh decomposition conditions, resulting in diverse decomposition outcomes that present significant challenges for downstream applications, especially for bioconversion. In this study, we demonstrate a hybrid biological-chemical conversion process for PE, converting its decomposition products, namely short-chain diacids, into a monomer, β-keto-δ-lactone (BKDL), for highly recyclable polydiketoenimine plastics using engineered Corynebacterium glutamicum.

Erratum: Ultrathin Metal-Organic-Layer Mediated Radiotherapy-Radiodynamic Therapy.

[This corrects the article PMC7442115.].

Automated Platform for the Plasmid Construction Process.

There is a growing need for applications capable of handling large synthesis biology experiments. At the core of synthetic biology is the process of cloning and manipulating DNA as plasmids. Here, we report the development of an application named DNAda capable of writing automation instructions for any given DNA construct design generated by the J5 DNA assembly program.

Improved polyketide production in C. glutamicum by preventing propionate-induced growth inhibition.

Corynebacterium glutamicum is a promising host for production of valuable polyketides. Propionate addition, a strategy known to increase polyketide production by increasing intracellular methylmalonyl-CoA availability, causes growth inhibition in C. glutamicum.

Reprogramming of Neutrophils as Non-canonical Antigen Presenting Cells by Radiotherapy-Radiodynamic Therapy to Facilitate Immune-Mediated Tumor Regression.

Ineffective antigen cross-presentation in the tumor microenvironment compromises the generation of antitumor immune responses. Radiotherapy-radiodynamic therapy (RT-RDT) with nanoscale metal-organic frameworks (nMOFs) induces robust adaptive immune responses despite modest activation of canonical antigen presenting dendritic cells. Here, using transplantable and autochthonous murine tumor models, we demonstrate that RT-RDT induces antitumor immune responses early neutrophil infiltration and reprogramming.

Bifunctional Metal-Organic Layers for Tandem Catalytic Transformations Using Molecular Oxygen and Carbon Dioxide.

Tandem catalytic reactions improve atom- and step-economy over traditional synthesis but are limited by the incompatibility of the required catalysts. Herein, we report the design of bifunctional metal-organic layers (MOLs), HfOTf-Fe and HfOTf-Mn, consisting of triflate (OTf)-capped Hf secondary building units (SBUs) as strong Lewis acidic centers and metalated TPY ligands as metal active sites for tandem catalytic transformations using O and CO as coreactants. HfOTf-Fe effectively transforms hydrocarbons into cyanohydrins via tandem oxidation with O and silylcyanation whereas HfOTf-Mn converts styrenes into styrene carbonates via tandem epoxidation and CO insertion.

Nanoscale Metal-Organic Layer Isolates Phthalocyanines for Efficient Mitochondria-Targeted Photodynamic Therapy.

Zinc-phthalocyanine (ZnPc) photosensitizers (PSs) have shown great potential in photodynamic therapy (PDT) owing to their strong absorption at long wavelengths (650-750 nm), high triplet quantum yields, and biocompatibility. However, the clinical utility of ZnPc PSs is limited by their poor solubility and tendency to aggregate in aqueous environments. Here we report the design of a new nanoscale metal-organic layer (nMOL) assembly, ZnOPPc@nMOL, with ZnOPPc [ZnOPPc = zinc(II)-2,3,9,10,16,17,23,24-octa(4-carboxyphenyl)phthalocyanine] PSs supported on the secondary building units (SBUs) of a Hf nMOL for PDT.

Nanoscale Metal-Organic Layers Detect Mitochondrial Dysregulation and Chemoresistance via Ratiometric Sensing of Glutathione and pH.

Mitochondrial dysregulation controls cell death and survival by changing endogenous molecule concentrations and ion flows across the membrane. Here, we report the design of a triply emissive nanoscale metal-organic layer (nMOL), NA@Zr-BTB/F/R, for sensing mitochondrial dysregulation. Zr-BTB nMOL containing Zr secondary building units (SBUs) and 2,4,6-tris(4-carboxyphenyl)aniline (BTB-NH) ligands was postsynthetically functionalized to afford NA@Zr-BTB/F/R by exchanging formate capping groups on the SBUs with glutathione(GSH)-selective (2)-1-(2'-naphthyl)-3-(4-carboxyphenyl)-2-propen-1-one (NA) and covalent conjugation of pH-sensitive fluorescein (F) and GSH/pH-independent rhodamine-B (R) to the BTB-NH ligands.

Metal-Organic Layers Hierarchically Integrate Three Synergistic Active Sites for Tandem Catalysis.

We report the design of a bifunctional metal-organic layer (MOL), Hf -Ru-Co, composed of [Ru(DBB)(bpy) ] [DBB-Ru, DBB=4,4'-di(4-benzoato)-2,2'-bipyridine; bpy=2,2'-bipyridine] connecting ligand as a photosensitizer and Co(dmgH) (PPA)Cl (PPA-Co, dmgH=dimethylglyoxime; PPA=4-pyridinepropionic acid) on the Hf secondary building unit (SBU) as a hydrogen-transfer catalyst. Hf -Ru-Co efficiently catalyzed acceptorless dehydrogenation of indolines and tetrahydroquinolines to afford indoles and quinolones. We extended this strategy to prepare Hf -Ru-Co-OTf MOL with a [Ru(DBB)(bpy) ] photosensitizer and Hf SBU capped with triflate as strong Lewis acids and PPA-Co as a hydrogen transfer catalyst.

Nanoscale metal-organic frameworks for x-ray activated in situ cancer vaccination.

Cancer vaccines have been actively pursued to bolster antitumor immunity. Here, we designed nanoscale metal-organic frameworks (nMOFs) as locally activable immunotherapeutics to release danger-associated molecular patterns (DAMPs) and tumor antigens and deliver pathogen-associated molecular patterns (PAMPs) for in situ personalized cancer vaccination. When activated by x-rays, nMOFs effectively generate reactive oxygen species to release DAMPs and tumor antigens while delivering CpG oligodeoxynucleotides as PAMPs to facilitate the maturation of antigen-presenting cells.

Ultrathin metal-organic layer-mediated radiotherapy-radiodynamic therapy enhances immunotherapy of metastatic cancers.

Checkpoint blockade immunotherapy (CBI) is effective in promoting a systemic immune response against some metastatic tumors. The reliance on the pre-existing immune environment of the tumor, however, limits the efficacy of CBI on a broad spectrum of cancers. Herein, we report the design of a novel nanoscale metal-organic layer (nMOL), Hf-MOL, for effective treatment of local tumors by enabling radiotherapy-radiodynamic therapy (RT-RDT) with low-dose X-rays and, when in combination with an immune checkpoint inhibitor, regression of metastatic tumors by re-activating anti-tumor immunity and inhibiting myeloid-derived suppressor cells.

Nanoscale Metal-Organic Frameworks Generate Reactive Oxygen Species for Cancer Therapy.

In the past 15 years, enormous progress has been made in cancer nanotechnology, and a several nanoparticles have entered clinical testing for cancer treatment. Among these nanoparticles are nanoscale metal-organic frameworks (nMOFs), a class of organic-inorganic hybrid nanomaterials constructed from metal binding sites and bridging ligands, which have attracted significant attention for their ability to integrate porosity, crystallinity, compositional and structural tunability, multifunctionality, and biocompatibility into a singular nanomaterial for cancer therapies. This Outlook article summarizes the progress on the design of nMOFs as nanosensitizers for photodynamic therapy (PDT), radiotherapy (RT), radiotherapy-radiodynamic therapy (RT-RDT), and chemodynamic therapy (CDT) via nMOF-mediated reactive oxygen species (ROS) generated under external energy stimuli or in the presence of endogenous chemical triggers.

Biomimetic nanoscale metal-organic framework harnesses hypoxia for effective cancer radiotherapy and immunotherapy.

Tumor hypoxia presents a major impediment to effective cancer therapy with ionizing radiation and immune checkpoint inhibitors. Here we report the design of a biomimetic nanoscale metal-organic-framework (nMOF), Hf-DBP-Fe, with catalase-like activity to decompose elevated levels of HO in hypoxic tumors to generate oxygen and hydroxyl radical. The generated oxygen attenuates hypoxia to enable radiodynamic therapy upon X-ray irradiation and fixes DNA damage while hydroxyl radical inflicts direct damage to tumor cells to afford chemodynamic therapy.

Nanoscale Metal-Organic Frameworks Stabilize Bacteriochlorins for Type I and Type II Photodynamic Therapy.

Herein we report the design of a bacteriochlorin-based nanoscale metal-organic framework, Zr-TBB, for highly effective photodynamic therapy via both type I and type II mechanisms. The framework of Zr-TBB stabilizes 5,10,15,20-tetra(-benzoato)bacteriochlorin (TBB) ligands toward oxygen and light via geometrical constraint. Upon 740 nm light irradiation, Zr-TBB efficiently generates various reactive oxygen species, including singlet oxygen, superoxide anion, hydrogen peroxide, and hydroxyl radicals, to afford superb antitumor efficacy on mouse models of breast and colon cancers, with cure rates of 40% and 60%, respectively.

Synergistic Effect over Sub-nm Pt Nanocluster@MOFs Significantly Boosts Photo-oxidation of N-alkyl(iso)quinolinium Salts.

Quinolones and isoquinolones are of interest to pharmaceutical industry owing to their potent biological activities. Herein, we first encapsulated sub-nm Pt nanoclusters into Zr-porphyrin frameworks to afford an efficient photocatalyst Pt@PCN-221. This catalyst can dramatically promote electron-hole separation and O generation to achieve synergistic effect first in the metal-organic framework (MOF) system, leading to the highest activity in photosynthesis of (iso)quinolones in >90.

Metal-Organic Layers for Synergistic Lewis Acid and Photoredox Catalysis.

We report the design of a new multifunctional metal-organic layer (MOL), Hf-Ir-OTf, comprising triflate (OTf)-capped Hf secondary building units (SBUs) and photosensitizing Ir(DBB)[dF(CF)ppy] [DBB-Ir-F, DBB = 4,4'-di(4-benzoato)-2,2'-bipyridine; dF(CF)ppy = 2-(2,4-difluorophenyl)-5-(trifluoromethyl)pyridine] bridging ligands. Hf-Ir-OTf effectively catalyzed dehydrogenative cross-couplings of heteroarenes with ethers, amines, and unactivated alkanes with turnover numbers of 930, 790, and 950, respectively. Hf-Ir-OTf also competently catalyzed late-stage functionalization of bioactive and drug molecules such as caffeine, Fasudil, and Metyrapone.

Multifunctional Nanoscale Metal-Organic Layers for Ratiometric pH and Oxygen Sensing.

As a monolayered version of nanoscale metal-organic frameworks (nMOFs), nanoscale metal-organic layers (nMOLs) represent an emerging class of highly tunable two-dimensional materials for hierarchical functionalization and with facile access to analytes. Here we report the design of the first nMOL-based biosensor for ratiometric pH and oxygen sensing in mitochondria. Cationic Hf-Ru nMOL was solvothermally synthesized by laterally connecting Hf secondary building units (SBUs) with oxygen-sensitive Ru(bpy)-derived DBB-Ru ligands (bpy = 2,2'-bipyridine).

A Nanoscale Metal-Organic Framework to Mediate Photodynamic Therapy and Deliver CpG Oligodeoxynucleotides to Enhance Antigen Presentation and Cancer Immunotherapy.

Checkpoint blockade immunotherapy (CBI) awakes a host innate immune system and reactivates cytotoxic T cells to elicit durable response in some cancer patients. Now, a cationic nanoscale metal-organic framework, W-TBP, is used to facilitate tumor antigen presentation by enabling immunogenic photodynamic therapy (PDT) and promoting the maturation of dendritic cells (DCs). Comprised of dinuclear W secondary building units and photosensitizing 5,10,15,20-tetra(p-benzoato)porphyrin (TBP) ligands, cationic W-TBP mediates PDT to release tumor associated antigens and delivers immunostimulatory CpG oligodeoxynucleotides to DCs.

Metal-Organic Layers as Multifunctional Two-Dimensional Nanomaterials for Enhanced Photoredox Catalysis.

Metal-organic layers (MOLs) have recently emerged as a novel class of molecular two-dimensional (2D) materials with significant potential for catalytic applications. Herein we report the design of a new multifunctional MOL, Hf-Ir-Ni, by laterally linking Hf secondary building units (SBUs) with photosensitizing Ir(DBB)[dF(CF)ppy] [DBB-Ir-F, DBB = 4,4'-di(4-benzoato)-2,2'-bipyridine; dF(CF)ppy = 2-(2,4-difluorophenyl)-5-(trifluoromethyl)pyridine] bridging ligands and vertically terminating the SBUs with catalytic Ni(MBA)Cl [MBA = 2-(4'-methyl-[2,2'-bipyridin]-4-yl)acetate] capping agents. Hf-Ir-Ni was synthesized in a bottom-up approach and characterized by TEM, AFM, PXRD, TGA, NMR, ICP-MS, UV-vis, and luminescence spectroscopy.

Low-dose X-ray radiotherapy-radiodynamic therapy via nanoscale metal-organic frameworks enhances checkpoint blockade immunotherapy.

Checkpoint blockade immunotherapy relies on energized cytotoxic T cells attacking tumour tissue systemically. However, for many cancers, the reliance on T cell infiltration leads to low response rates. Conversely, radiotherapy has served as a powerful therapy for local tumours over the past 100 years, yet is rarely sufficient to cause systemic tumour rejection.

Nanoscale Metal-Organic Framework Hierarchically Combines High-Z Components for Multifarious Radio-Enhancement.

With tunability and porosity, nanoscale metal-organic frameworks (nMOFs) can incorporate multiple components to realize complex functions for biomedical applications. Here we report the synthesis of W@Hf-DBB-Ir, a new nMOF assembly hierarchically incorporating three high-Z components-Hf-based metal-oxo clusters, Ir-based bridging ligands, and W-based polyoxometalates (POMs)-as a multifarious radioenhancer. Cationic Hf-DBB-Ir was built from Hf secondary building units (SBUs) and [Ir(bpy)(ppy)] (bpy = 2,2'-bipyridine, ppy = 2-phenylpyridine) derived dicarboxylate ligands (DBB-Ir) and then loaded with Wells-Dawson-type [PWO] (W) POMs to afford W@Hf-DBB-Ir.