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Sonodynamic therapy (SDT), utilizing ultrasound (US) as the trigger, has gained popularity recently as a therapeutic approach with significant potential for treating various diseases. Metal-organic frameworks (MOFs), characterized by structural flexibility, are prominently emerging in the SDT realm as an innovative type of sonosensitizer, offering functional tunability and biocompatibility. However, due to the inherent limitations of MOFs, such as low reactivity to reactive oxygen species and challenges posed by the complex tumor microenvironment, MOF-based sonosensitizers with singular functions are unable to demonstrate the desired therapeutic efficacy and may pose risks of toxicity, limiting their biological applications to superficial tissues. MOFs generally possess distinctive crystalline structures and properties, and their controlled coordination environments provide a flexible platform for exploring structure-effect relationships and guiding the design and development of MOF-based nanomaterials to unlock their broader potential in biological fields. The primary focus of this paper is to summarize cases involving the modification of different MOF materials and the innovative strategies developed for various complex conditions. The paper outlines the diverse application areas of functionalized MOF-based sonosensitizers in tumor synergistic therapies, highlighting the extensive prospects of SDT. Additionally, challenges confronting SDT are briefly summarized to stimulate increased scientific interest in the practical application of MOFs and the successful clinical translation of SDT. Through these discussions, we strive to foster advancements that lead to early-stage clinical benefits for patients. STATEMENT OF SIGNIFICANCE: 1. An overview for the progresses in SDT explored from a novel and fundamental perspective. 2. Different modification strategies to improve the MOFs-mediated SDT efficacy are provided. 3. Guidelines for the design of multifunctional MOFs-based sonosensitizers are offered. 4. Powerful tumor ablation potential is reflected in SDT-led synergistic therapies. 5. Future challenges in the field of MOFs-based SDT in clinical translation are suggested., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)

Chemodynamic therapy (CDT) strategies rely on the generation of reactive oxygen species (ROS) to kill tumor cells, with hydroxyl radicals ( • OH) serving as the key mediators of cytotoxicity in this setting. However, the efficacy of CDT approaches is often hampered by the properties of the tumor microenvironment (TME) and associated limitations to the Fenton reaction that constrains ROS generation. As such, there is a pressing need for the design of new nanoplatforms capable of improving CDT outcomes. In this study, an Fc-based metal-organic framework (MOF) vitamin k3 (Vk3)-loaded cascade catalytic nanoplatform (Vk3@Co-Fc) was developed. This platform was capable of undergoing TME-responsive degradation without impacting normal cells. After its release, Vk3 was processed by nicotinamide adenine dinucleotide hydrogen phosphate (NAD(P)H) quinone oxidoreductase-1 (NQO1), which is highly expressed in tumor cells, thereby yielding large quantities of H 2 O 2 that in turn interact with Fe ions via the Fenton reaction to facilitate in situ cytotoxic • OH production. This process leads to immunogenic cell death (ICD) of the tumor, which then promotes dendritic cell maturation and ultimately increases T cell infiltration into the tumor site. When this nanoplatform was combined with programmed death 1 (PD-1) checkpoint blockade approaches, it was sufficient to enhance tumor-associated immune responses in breast cancer as evidenced by increases in the frequencies of CD45 + leukocytes and CD8 + cytotoxic T lymphocytes, thereby inhibiting tumor metastasis to the lungs and improving murine survival outcomes. Together, this Vk3@Co-Fc cascading catalytic nanoplatform enables potent cancer immunotherapy for breast cancer regression and metastasis prevention.

Luminescent metal organic frameworks (LMOFs) are considered to be a type of promising optical sensing material due to their designable and tunable functions, and stable pore structures. Therefore, the preparation of LMOFs has become a research hotspot in recent years. As we know, triazine carboxylic acid ligands are conducive for constructing LMOF materials due to their large π electron conjugated system. In this work, two crystalline materials [Cd 3 (TCPT) 2 ]·0.5DMF·4H 2 O (1) and (H 3 O)[Zn 2 (TCPT)(μ 2 -OH) 2 ]·0.5DMF·3H 2 O (2) were obtained by the reaction of the triazine carboxylic acid ligand 2,4,6-tris(4-carboxyphenoxy)-1,3,5-triazine (H 3 TCPT), as an extended carboxylate arm, and d 10 transition metal salts. Their structures were determined by single crystal X-ray diffraction and characterized by infrared spectroscopy (IR), ultraviolet visible spectroscopy (UV-vis), fluorescence spectroscopy, powder X-ray diffraction (PXRD) and thermogravimetric analysis (TG). The experimental results showed that complexes 1 and 2 show excellent fluorescent emission behavior. Thus, we explored their fluorescence sensing properties. To our delight, the results showed that they both had the ability to sense small organic drug molecules and aromatic amine molecules containing o -phenylenediamine (OPD), m -phenylenediamine (MPD) and p -phenylenediamine (PPD). In general, the practical applications of a MOF material are usually limited because of the relatively harsh synthesis methods. In this aspect, we studied the synthesis method in detail to obtain the optimal reaction conditions for the large-scale synthesis of 1 and 2. The preparation of the two LMOF materials only required about 3 hours of heating time and they could be prepared on a large scale, which is significant for the practical applications of LMOFs.

Metal-organic frameworks (MOFs) have shown significant potential as photocatalysts. It has been widely assumed that all catalytic active sites within MOFs are functional in photocatalytic reactions but for a three-dimensional MOF, whether the internal catalytic active sites can effectively absorb light and actively contribute to photocatalytic reactions remains to be explored. In this context, we synthesized a two-dimensional nanosheet MOF (2D-MOF) and a three-dimensional bulk MOF (3D-MOF) composed of Zr6 clusters and tetracarboxylic porphyrin (TCPP) by the approach described in the literature. Re(bpy)(CO)3Cl (bpy = 2,2′-bipyridine), which has remarkable CO2 photoreduction ability, was introduced to the two MOFs to create two new photocatalysts 2D-MOF-Re and 3D-MOF-Re, respectively. Photocatalytic CO2 reduction experiments show that based on the equal number of catalytic active sites, the CO turnover number (TON) of 2D-MOF-Re reaches 27.8 in 6 h, which is 50 times that of 3D-MOF-Re. The result shows that certain catalytic active sites inside the bulk MOF are inactive due to the inability to absorb light. This study illuminates the potential of the dimensional reduction approach in the design of photocatalysts to exploit the capabilities fully. [ABSTRACT FROM AUTHOR]

Luminescent metal organic frameworks (LMOFs) are considered to be a type of promising optical sensing material due to their designable and tunable functions, and stable pore structures. Therefore, the preparation of LMOFs has become a research hotspot in recent years. As we know, triazine carboxylic acid ligands are conducive for constructing LMOF materials due to their large π electron conjugated system. In this work, two crystalline materials [Cd3(TCPT)2]·0.5DMF·4H2O (1) and (H3O)[Zn2(TCPT)(μ2-OH)2]·0.5DMF·3H2O (2) were obtained by the reaction of the triazine carboxylic acid ligand 2,4,6-tris(4-carboxyphenoxy)-1,3,5-triazine (H3TCPT), as an extended carboxylate arm, and d10 transition metal salts. Their structures were determined by single crystal X-ray diffraction and characterized by infrared spectroscopy (IR), ultraviolet visible spectroscopy (UV-vis), fluorescence spectroscopy, powder X-ray diffraction (PXRD) and thermogravimetric analysis (TG). The experimental results showed that complexes 1 and 2 show excellent fluorescent emission behavior. Thus, we explored their fluorescence sensing properties. To our delight, the results showed that they both had the ability to sense small organic drug molecules and aromatic amine molecules containing o-phenylenediamine (OPD), m-phenylenediamine (MPD) and p-phenylenediamine (PPD). In general, the practical applications of a MOF material are usually limited because of the relatively harsh synthesis methods. In this aspect, we studied the synthesis method in detail to obtain the optimal reaction conditions for the large-scale synthesis of 1 and 2. The preparation of the two LMOF materials only required about 3 hours of heating time and they could be prepared on a large scale, which is significant for the practical applications of LMOFs. [ABSTRACT FROM AUTHOR]

Improving proton conductivity and fabricating viable metal‐organic frameworks (MOFs) based proton exchange membranes (PEMs) are central issues exploiting electrolyte MOFs. We aim to design multivariate flexibility synergistic strategy to achieve Flexible MOFs (FMOFs) with high conductivity at a wide range of humidity. In situ powder X‐ray diffraction (PXRD) and temperature‐dependent Fourier transform infrared spectra (FT‐IR) prove the synergistic self‐adaption between dynamic torsion of alkyl sulfonic acid and dynamic breathing of FMOF, forming a continuous hydrogen‐bonding networks to maintain high conductivity. Based on the convincing proton conductivity, we construct a series of long‐term durable MOF‐based PEMs that serve as a bridge between MOF and fuel cell. Consequently, the membrane electrode assembly (MEA) of the flexible PMNS1‐40 exhibits a maximum single‐cell power density of 34.76 mW cm−2 and hopefully opens doors to evaluate the practical application of proton‐conducting MOFs in direct methanol fuel cells. [ABSTRACT FROM AUTHOR]

Considering that cyclotriphosphazene polycarboxylic acid is a kind of organic ligand with fantastic structures and performances and the unique luminescence characteristics of rare earth ions, a series of porous lanthanide metal–organic frameworks (Ln-MOFs) (CH3)2NH2[Ln3(HCPCP)1.5(CH3COO)]·6DMA (Ln = Ce (1), Sm (2), Eu (3), Tb (4), HCPCP = hexa(4-carboxyphenoxy)cyclotriphosphazene, and DMA = N,N-dimethylacetamide) were synthesized with novel topological network structures. Compound 4 exhibited a sensitive recognition of –NO2, and had a fluorescence quenching phenomenon for seven kinds of nitro aromatic compounds (NACs). In particular, it showed the best fluorescence response to 2,4,6-trinitrophenol (TNP) and 2,4-dinitrophenol (DNP), and the KSV values were 2.86 × 105 M−1 and 8.21 × 104 M−1, and the limit of detection (LOD) values were 0.20 μM and 0.71 μM, respectively. At the same time, we successfully doped different concentrations of Eu3+ into compound 4 to obtain a series of doped Ln-MOF materials x%Eu3+@4 (x = 0.5, 2.5, 5, 7.5, 10, 15 and 20). With the increase of Eu3+ doping ratios, the characteristic peaks of Tb3+ and Eu3+ changed regularly, and the energy transfer from Tb3+ to Eu3+ ions occurred. By changing the excitation wavelength of the samples with different Eu3+ doping concentrations, a higher quality white light emitting material 7.5%Eu3+@4 (λex = 340 nm) was finally obtained, with a CIE coordinate of (0.3268, 0.3212). [ABSTRACT FROM AUTHOR]

The field of post‐synthesis modification has aroused widespread concern from diverse perspectives, including chemistry, biology, and material science. Post‐synthesis modification can introduce rich functionality into metal–organic frameworks (MOFs) without destroying the main structure of MOFs. Based on this research status, a series of lanthanide metal–organic frameworks ([Ln2(NH2‐BDC)2.5(CH3COO)(DMA)(H2O)]•DMA, Ln = Pr, Nd, Sm, Eu, Gd and Tb, NH2‐BDC = 2‐aminoterephthalic acid, DMA = N,N‐Dimethylacetamide) with 3D network structures, are synthesized by hydrothermal synthesis. Due to the presence of uncoordinated amino groups in the ligands, a series of post‐synthesis modified compounds are successfully synthesized through aldimine condensation reaction. Based on the good fluorescence properties and stable structure of coordination polymers and post‐synthesis modified compounds in water or organic solvents, they are able to be used as potential fluorescence sensor for the detection of Th4+, UO22+, and Cr2O72−, and the calculation result shows that the post‐synthesis modified compounds are more sensitive to the detection of analytes (Th4+, UO22+ and Cr2O72−) than coordination polymers. In addition, the MOF membrane prepared by self‐assembly of [Eu2(NH2‐BDC)2.5(CH3COO)(DMA)(H2O)]•DMA and ternary soap‐free copolymer (VAc‐AA‐BA) emulsion can be used first for detecting aldehyde vapors. [ABSTRACT FROM AUTHOR]

The transmembrane diffusion of soluble lithium polysulfides (LiPS) is the main cause of capacity loss and negative electrode corrosion in lithium-sulfur (Li-S) batteries. In order to suppress the shuttle effect of LiPS, a selective permeability membrane was constructed by introducing functional materials with negative charge groups. Herein, a functional separator with high ion conductivity is obtained by casting the environmentally friendly MOF material sulfonic acid functionalized amino-MIL-101 (S-MIL-101) onto the separator. It is found that the functionalized sulfonic acid group not only accelerates the conduction of the lithium-ion but also repels the polysulfide anion through electrostatic interactions. With this functionalized separator, the initial capacity of batteries is 1444.6 mAh·g−1 at 0.2C and remains 990.4 mAh·g−1 after 100 cycles. Meanwhile, the batteries still deliver a high initial discharge capacity of 895.7 mAh·g−1 even with the high-sulfur-loading cathode (4.7 mg cm−2) at 0.2C. We designed and synthesized sulfonic acid functionalized Al-based MIL-101-NH 2 modified separator for lithium-sulfur batteries. The introduction of sulfonic acid groups can accelerate the conduction of Li+ and carry out electrochemical processes. Besides, negatively charged sulfonic acid groups can suppress the shuttle effect through electrostatic interaction. The lithium-sulfur batteries assembled with the S-MIL-101 separator have an initial discharge capacity of 895.7 mAh·g−1 at 0.2C with 4.7 mg cm−2. [Display omitted] • S-MIL-101 improves Li+ conductivity. • Modified separators inhibit shuttle effect. • Modified separators inhibit shuttle effect. [ABSTRACT FROM AUTHOR]

• MOF-based nanosonosensitizers was fabricated with defect-rich Ti-based MOF, platinum nanoparticles and the O 2 carrier PFOB. • MOF-based nanosonosensitizers produced high levels of 1O 2 and induced ICD. • MOF-based nanosonosensitizers enhanced sono-immunotherapy against both primary tumors and metastatic tumors. Sonodynamic therapy (SDT) has emerged as a promising strategy for treating tumors owing to its non-invasiveness and high tissue-penetrating depth. Improving the efficiency of electron-hole separation of sonosensitizers and alleviation of the hypoxic tumor microenvironment remain major challenges. Metal-organic frameworks (MOFs) have greatly potential in SDT application, however, exploring new sonosensitizers with high reactive oxygen species (ROS) generation and improving the efficacy through a synergistic effect in combination with other therapeutic modalities remain major challenges. Furthermore, the immunosuppressive tumor microenvironment (TME) is characterized by hypoxia, which limit the efficacy of O 2 -dependent cancer treatments including SDT and immunotherapy. Herein, we fabricated a defect-rich titanium-based MOFs using propionic acid-mediated self-templated hierarchical etching. Reductive platinum nanoparticles were embedded onto the surface of MOFs to enhance the spatial separation of electron-hole pairs and improve the quantum yield of ultrasound-generated singlet oxygen (1O 2). Finally, perfluorobromooctane was encapsulated in the MOFs to function as an oxygen carrier to develop an oxygen self-feeding nanosensitizer. In vitro and in vivo assays demonstrated that this nanoplatform could produce high levels of 1O 2 under ultrasound irradiation, which led to enhanced SDT. Moreover, this nanoplatform also relieved the immunosuppressive TME by overcoming hypoxia and enhancing immunogenic cell death to promote the infiltration of tumor-specific cytotoxic T cells into the immunologically "cold" tumor. Therefore, combination of nanoplatform-mediated SDT with anti-PDL1 antibodies effectively inhibited the primary tumors, as well as the metastatic tumors. This study provides an insightful strategy for improving SDT and broadens the application of MOF-based sonosensitizers for sono-immunotherapy. [ABSTRACT FROM AUTHOR]

Inorganic pyrophosphate (P 2 O 7 4−, PPi) plays a vital role in a variety of metabolic processes, therefore, the development of a highly sensitive and selective detection method for PPi is of great significance. In this work, a fluorescence sensor based on luminescence metal-organic frameworks (LMOFs) via covalent post-synthetic modification (PSM) was prepared and applied to the fluorescence detection of PPi. The sensor with high fluorescence quantum yield was synthesized based on Schiff base reaction between 2-pyridinecarboxaldehyde (2-PC) and TMU-17-NH 2. It was designed according to the strong binding affinity between metal ion and PPi, and Cu2+ was selected as the mediating ion in this experiment. The fluorescence of TMU-PC is quenched by Cu2+ through photoelectron transfer (PET) mechanism, and the quenched fluorescence can be restored after adding PPi, forming an "on-off-on" fluorescence sensor, which can realize the sequential detection of Cu2+ and PPi. TMU-PC sensor has the advantages of fast response time, wide linear range, high sensitivity, and high specificity for PPi detection, and can be constructed as a fluorescence IMPLICATION logic gate. This work is the first attempt to prepare LMOFs via PSM for fluorescence detection of PPi, which has excellent application prospects for the clinical detection of related diseases. [Display omitted] • It is the first attempt to prepare LMOFs via PSM for PPi fluorescence detection. • An "on-off-on" fluorescence platform was designed based on the mediating ion Cu2+. • The detection was completed within 30 s with high specificity for PPi. • The sensor was used to detect PPi in human urine and synovial fluid samples. [ABSTRACT FROM AUTHOR]

• A composite material Cu-BTC@H4TBAPy assembled by Cu-BTC and H4TBAPy. • Superior luminescence property shows potential applications in fluorescence sensing. • A role of fluorescent sensor switch in recognition of Al3+ and Fe3+. A kind of metal organic framework composite material was prepared by encapsulating chemical chromophore the 1,3,6,8-tetrakis(p-benzoic acid)pyrene (H 4 TBAPy) in Cu-BTC which has the large square-shaped pores, a reasonable degree of thermal stability and a capacity for chemical functionalization of the channel linings. Cu-BTC@H 4 TBAPy has superior luminescence performance than framework material Cu-BTC (H 3 BTC = 1, 3, 5-trimellitic acid). Base on its luminescence property, we performed fluorescence sensing experiments on heavy metal ions. The results show that the metal ion Fe3+ has a significant turn-off effect on Cu-BTC@H 4 TBAPy, while Al3+ has a significant turn-on effect on Cu-BTC@H 4 TBAPy. This indicates that Cu-BTC@H 4 TBAPy can play a role of fluorescent sensor switch in recognition of different ions. [Display omitted] [ABSTRACT FROM AUTHOR]

Three MM-MOFs based on the reaction of H 6 TTHA ligand, Ln(NO 3) 3 ·6H 2 O (Ln=Eu, Sm, Dy) and Zn(NO 3) 2 ·6H 2 O under hydrothermal conditions. Complex 1 had the fluorescence sensing abilities for metal ions, anions, and organic nitro compounds. It was worth noting that complex 1 showed prominent sensitivity for TNP, the detection limit was as low as 1.14 μM. [Display omitted] Metal-organic frameworks composed of two metals in the structure are called mixed-metal metal organic frameworks (MM-MOFs). In this work, we constructed three MM-MOFs, namely [Zn 3 Eu 2 (TTHA) 2 (H 2 O) 6 ]·6H 2 O (1), [Zn 3 Sm 2 (TTHA) 2 (H 2 O) 6 ]·2H 2 O (2) and [ZnDy(HTTHA)(H 2 O) 4 ]·2H 2 O (3) by the reaction of H 6 TTHA ligand (H 6 TTHA = 1, 3, 5-triazine-2, 4, 6-triamine hexaacetic acid), Ln(NO 3) 3 ·6H 2 O (Ln = Eu, Sm, Dy) and Zn(NO 3) 2 ·6H 2 O under hydrothermal conditions. The complexes 1 – 2 were a 3D microporous structure and complex 3 formed a 3D network structure. Furthermore, complex 1 exhibited excellent fluorescence properties. We explored the fluorescence sensing abilities of complex 1 for metal ions, anions, and organic nitro compounds. The experimental results showed that complex 1 could sensitively and efficiently detect Fe3+, Cr 2 O 7 2- ions and 2,4,6-trinitrophenol (TNP). It was worth noting that complex 1 showed prominent sensitivity for TNP, the detection limit was as low as 1.14 μM. [ABSTRACT FROM AUTHOR]

Luminescent metal-organic frameworks (LMOFs) have become an important class of fluorescence sensing materials, whereas direct applications of LMOFs for identifying analytes still remain a challenge. Post synthetic modification (PSM) is an effective strategy to improve the performance of LMOFs. In this work, PSM of UiO-66-NH 2 was achieved with 4-carboxyphenylboronic (4-CPBA), based on which a fluorescence sensor, UiO-CPBA, was designed. The sensor was synthesized in the off state utilizing the photo-induced electron transfer (PET) process caused by the introduction of 4-CPBA and applied to the recognition of sialic acid (SA). The interaction between the boric acid group and the triol side chain of SA interrupted the PET process and turned on the fluorescence, thus fluorescence detection of SA was realized. This method exhibited a linear range of 1–100 μM and a limit of detection (LOD) of 0.15 μM for SA determination. The analysis of human serum verified the practicability of UiO-CPBA for SA, giving a new way for the construction of SA sensing platforms toward complex real samples. [Display omitted] • A turn-on fluorescence sensor was designed by PSM of MOFs with 4-CPBA. • PSM-MOFs were used for the fluorescence detection of sialic acid for the first time. • The sensor exhibited high sensitivity and specificity toward sialic acid. [ABSTRACT FROM AUTHOR]

1 A new Ln-BTC-Ac-FM framework intelligent materials 2 High sensitivity and selectivity to UO 2 2+ in aqueous solution. 3 Better adsorption effects on Coomassie Brilliant Blue (CBB) and Eosin The unique fluorescence properties of rare earth ions and subtle interactions with organic ligands make the target lanthanide metal-organic frameworks show potential development prospects in many fields. Based on this situation, a series of new lanthanide metal-organic frameworks Ln-BTC-AC-FM: (CH 3) 2 NH 2 [Ln 2 (BTC)(AC) 3 (FM)], (Ln=Pr (1), Ce (2), Nd (3), Eu (4), Sm (5), Gd (6), Tb (7), Ho (8), Er (9) and Yb (10), H 3 BTC=1,3,5-benzenetricarboxylic acid) were synthesized through the reaction of triangular polycarboxylic acid ligand (H 3 BTC) and rare earth nitrate Ln(NO 3) 3 ·6H 2 O with mixed formic acid (FM) and glacial acetic acid (AC) system. Due to this new type of Ln-BTC-AC-FM MOFs have unique and excellent fluorescence properties, we selected (CH 3) 2 NH 2 [Eu 2 (BTC)(AC) 3 (FM)] (4) to explore its detection performance for UO 2 2+ in aqueous solution. The study found that 4 is a high-efficiency fluorescent probe, which has a good quenching effect on uranium solution, and the quenching rate can reach 98.01%. At the same time, 4 has a good fluorescent response to UO 2 2+, with a higher K SV value of 8.56 × 103 M−1 and a lower detection limit of 4.12 μM. In addition, we also studied the adsorption properties of this series of Ln-BTC-AC-FM MOFs for dyes because of their novel three-dimensional microporous structures. The results showed that 4 has a good adsorption effect on Coomassie Brilliant Blue (CBB) and Eosin. Moreover, it was found that the dye adsorption process was proved to be a suitable pseudo-second-order kinetic model. [Display omitted] [ABSTRACT FROM AUTHOR]