In this review, the recent advancements of POMOFs and POMOPs, including their assembly methodologies, classification and related applications are summarized. Moreover, the current challenges in the ...design and fabrication of POMOFs and POMOPs as well as the great potential in these two areas are also discussed.
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•The recent advancements of POMOFs and POMOPs are summarized.•The advantages of using POM clusters to construct POMOFs and POMOPs are summarized.•Synthetic strategies for further development of POMOFs and POMOPs are presented.•Understanding the structure-property relationships of POMOFs and POMOPs.•The current challenges and the great potential of POMOFs and POMOPs are discussed.
During the past two decades, the search of strategies to introduce polyoxometalate (POM) clusters as secondary building units (SBUs) to construct porous extended POM-organic frameworks (POMOFs) and discrete POM-organic polyhedra (POMOPs) have attracted sustained interests because such materials not only integrate the advantages of both POMs and framework/polyhedra structures, but also exhibit good prospects in photo-/electro-catalysis, separation, molecular recognition, host-guest chemistry and so on. In this review, the recent advancements of POMOFs and POMOPs, including their assembly methodologies, classification and related applications are summarized. Moreover, the current challenges in the design and fabrication of POMOFs and POMOPs as well as the great potential in these two areas are also discussed.
A protein‐sized (ca. 4.2×4.2×3.6 nm3) non‐biologically derived molecule {Nb288O768(OH)48(CO3)12} (Nb288) containing up to 288 niobium atoms has been obtained, which is by far the largest and the ...highest nuclearity polyoxoniobate (PONb). Particularly, in terms of metal nuclearity number, Nb288 is the second largest cluster so far reported in classic polyoxometalate chemistry (V, Mo, W, Nb, and Ta). Nb288 can be described as a giant windmill‐like cluster aggregate of six nanoscale high‐nuclearity PONb units {Nb47O128(OH)6(CO3)2} (Nb47) joined together by six additional Nb ions. Interestingly, the 47‐nuclearity Nb47 units generated in situ can be isolated and bridged by copper complexes to form an inorganic–organic hybrid three‐dimensional PONb framework, which exhibits effective catalytic activity for hydrolyzing nerve agent simulant of dimethyl methylphosphonate. The unique Nb47 cluster also provides a new type of topology to very limited family of Nb‐O clusters.
Friendly niobium giant: An unprecedentedly huge polyoxoniobate (PONb) with as many as 288 Nb centers has been made. This is by far the largest PONb and the second highest nuclearity polyoxometalate reported to date. It incorporates a unique 47‐nuclearity PONb building unit formed in situ, which can be stabilized by metal complexes to form an extended PONb framework with the capability of hydrolyzing dimethyl methylphosphonate.
Helical morphologies are widely observed in nature, however, it is very challenging to prepare artificial helical polymers. Especially, precisely understanding the structure information of artificial ...metal‐free helical covalent inorganic polymers via single‐crystal X‐ray diffraction (SCXRD) analysis is rarely explored. Here, we successfully prepare a novel metal‐free helical covalent inorganic polymer ({Te(C6H5)2 PO3(OH)}n, named CityU‐10) by introducing angular anions (HOPO32−) into traditional tellurium‐oxygen chains. The dynamic reversibility of the reaction is realized through the introduction of organic tellurium precursor and the slow hydrolysis of polyphosphoric acid. High‐quality and large‐size single crystals of CityU‐10 have been successfully characterized via SCXRD, where the same‐handed helical inorganic polymer chains form a pseudo‐two‐dimensional layer via multiple hydrogen‐bonding interactions. The left‐handed layers and right‐handed layers alternatively stack together through weak hydrogen bonds to form a three‐dimensional supramolecular structure. The single crystals of CityU‐10 are found to display promising optical properties with a large birefringence. Our results would offer new guidelines for designing and preparing new crystalline covalent polymers through tellurium‐based chemistry.
A metal‐free helical covalent inorganic polymer (CityU‐10) has been successfully prepared. Its crystal structure shows that the same‐handed helical chains form a pseudo‐two‐dimensional layer via multiple hydrogen‐bonding interactions. Then, the left‐handed layers and right‐handed layers alternatively stack together to form a three‐dimensional supramolecular structure.
Pheochromocytoma and paraganglioma (PPGL) are rare neuroendocrine tumors arising from adrenal and extra-adrenal chromaffin cells. They produce excessive amounts of catecholamines and their ...metabolites. A newly analytical procedure based on the semi-automated microextraction by packed sorbent (MEPS) technique, using a digitally controlled syringe (eVol) combined with liquid chromatography-tandem mass spectrometry (LC-MS/MS), was developed to quantify free urinary catecholamines and metanephrines. The important parameters affecting MEPS performance, namely the type of sorbent material (porous graphitized carbon (PGC), polar enhanced polymer (PEP), cation-exchange (CX) and C18), number of extraction cycles, and elution solvent system, were evaluated. The optimal experimental conditions involved the loading of sample mixture in seven extraction cycles through a C18 sorbent in a MEPS syringe, followed by using elution solutions (water/acetonitrile/formic acid, 95/4.75/0.25). The entire sample preparation took about 4 min. Chromatographic separation was well achieved with an HSS PFP column using the gradient elution. The linearity range of the method was 0.167–33.4 ng/mL for epinephrine, 0.650–130 ng/mL for norepinephrine, 1.53–306 ng/mL for dopamine, 1.34–268 ng/mL for metanephrine, 3.43–686 ng/mL for normetanephrine, and 1.33–265 ng/mL for 3-methoxytyramine. The intra- and interassay precisions were ≤ 12.8%, and the respective accuracies were 88.4–112.0% and 89.0–109.5%. The carryover and sample stability without acidification were also investigated. Validation using clinical urine specimens showed that the proposed method had higher sensitivity compared with other urinary biochemical tests. The developed MEPS-LC-MS/MS method was simple, fast, and cost-effective; it helped to obtain information about multiple metabolites. It is applicable in routine clinical laboratories for the screening of PPGL.
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The metabolome includes not just known but also unknown metabolites; however, metabolite annotation remains the bottleneck in untargeted metabolomics. Ion mobility - mass spectrometry (IM-MS) has ...emerged as a promising technology by providing multi-dimensional characterizations of metabolites. Here, we curate an ion mobility CCS atlas, namely AllCCS, and develop an integrated strategy for metabolite annotation using known or unknown chemical structures. The AllCCS atlas covers vast chemical structures with >5000 experimental CCS records and ~12 million calculated CCS values for >1.6 million small molecules. We demonstrate the high accuracy and wide applicability of AllCCS with medium relative errors of 0.5-2% for a broad spectrum of small molecules. AllCCS combined with in silico MS/MS spectra facilitates multi-dimensional match and substantially improves the accuracy and coverage of both known and unknown metabolite annotation from biological samples. Together, AllCCS is a versatile resource that enables confident metabolite annotation, revealing comprehensive chemical and metabolic insights towards biological processes.
Herein, a giant Sb‐rich polyoxometalate (POM) {Sb21Tb7W56} is reported, which contains the largest number of Sb atoms in a POM so far. The Sb‐rich POM has many interesting structural features and is ...a rare example of a soluble and water‐stable giant POM. Biomedical studies indicate that the Sb‐rich POM exhibits broad‐spectrum antitumor activity against various cancer cell lines by reactivating the P53‐dependent apoptotic processes and disrupting the mitochondrial membrane. In addition, this Sb‐rich POM was capable of suppressing the growth and metastasis of a breast cancer in vivo. This work demonstrates that Sb‐rich POMs are promising candidates for the development of new anticancer drugs.
A novel soluble and water‐stable giant Sb‐rich polyoxometalate (POM) has been developed, which shows the largest Sb−Ln−W cluster and has the greatest number of Sb centers in a cluster yet found in POM chemistry. Importantly, the Sb‐rich POM can exhibit broad‐spectrum antitumor and anti‐metastatic activities in vitro and in vivo without causing adverse effects, making it a promising candidate for a antitumor agent.
The combination of polyoxoniobates (PONbs) with 3d metal ions, azoles, and organoamines is a general synthetic procedure for making unprecedented PONb metal complex cage materials, including discrete ...molecular cages and extended cage frameworks. By this method, the first two PONb metal complex cages K4@{Cu29(OH)7(H2O)2(en)8(trz)21Nb24O67(OH)2(H2O)34} and Cu(en)2@{Cu2(en)2(trz)26(Nb68O188)} have been made. The former exhibits a huge tetrahedral cage with more than 120 metal centers, which is the largest inorganic–organic hybrid PONb known to date. The later shows a large cubic cage, which can act as building blocks for cage‐based extended assembly to form a 3D cage framework {Cu(en)2@{Cu2(trz)2(en)26H10Nb68O188}}. These materials exhibit visible‐light‐driven photocatalytic H2 evolution activity and high vapor adsorption capacity. The results hold promise for developing both novel cage materials and largely unexplored inorganic–organic hybrid PONb chemistry.
Hybrid polyoxoniobate cages: A series of polyoxoniobate (PONb) metal complex cage materials have been made, thus fusing two areas, namely PONbs and MOFs. The cage materials are by far the largest inorganic–organic hybrid PONbs and hold promise for the developments of both novel cage materials and largely unexplored inorganic–organic hybrid PONb chemistry.
Large-scale metabolite annotation is a challenge in liquid chromatogram-mass spectrometry (LC-MS)-based untargeted metabolomics. Here, we develop a metabolic reaction network (MRN)-based recursive ...algorithm (MetDNA) that expands metabolite annotations without the need for a comprehensive standard spectral library. MetDNA is based on the rationale that seed metabolites and their reaction-paired neighbors tend to share structural similarities resulting in similar MS2 spectra. MetDNA characterizes initial seed metabolites using a small library of MS2 spectra, and utilizes their experimental MS2 spectra as surrogate spectra to annotate their reaction-paired neighbor metabolites, which subsequently serve as the basis for recursive analysis. Using different LC-MS platforms, data acquisition methods, and biological samples, we showcase the utility and versatility of MetDNA and demonstrate that about 2000 metabolites can cumulatively be annotated from one experiment. Our results demonstrate that MetDNA substantially expands metabolite annotation, enabling quantitative assessment of metabolic pathways and facilitating integrative multi-omics analysis.
Hepatocellular carcinoma (HCC) is the fifth most common and the third most deadly malignant tumor worldwide. Hypoxia and related oxidative stress are heavily involved in the process of HCC ...development and its therapies. However, direct and accurate measurement of oxygen concentration and evaluation of hypoxic effects in HCC prove difficult. Moreover, the hypoxia-mediated mechanisms in HCC remain elusive. Here, we summarize recent major evidence of hypoxia in HCC lesions shown by measuring partial pressure of oxygen (pO
), the clinical importance of hypoxic markers in HCC, and recent advances in hypoxia-related mechanisms and therapies in HCC. For the mechanisms, we focus mainly on the roles of oxygen-sensing proteins (i.e., hypoxia-inducible factor and neuroglobin) and hypoxia-induced signaling proteins (e.g., matrix metalloproteinases, high mobility group box 1, Beclin 1, glucose metabolism enzymes, and vascular endothelial growth factor). With respect to therapies, we discuss mainly YQ23, sorafenib, 2-methoxyestradiol, and celastrol. This review focuses primarily on the results of clinical and animal studies.
Cup‐shaped molecules are of great interest due to their appealing architectures and properties. Compared with widely studied calixarenes, polyoxometalate‐based cup‐shaped molecules currently remain a ...virgin land waiting for exploration. In this work, we report the first discovery of two giant cup‐shaped inorganic–organic hybrid polyoxoniobates (PONbs) of {Cu12Nb120} and {Cd16Nb128}. The former integrates three tricyclic Nb24 clusters and a hexacyclic Nb48 cluster into a cup‐shaped molecule via a Cu12 metallacalixarene, while the latter unifies two tricyclic Nb24 clusters and a brand‐new pentacyclic Nb40 cluster into another cup‐shaped molecule via a hybrid Cd16 unit. With 132 and 144 metal centers, {Cu12Nb120} and {Cd16Nb128} show the largest two inorganic–organic hybrid PONbs known to date.
Calixarene‐like polyoxoniobates: Two unprecedented giant calixarene‐like polyoxoniobate (PONb) nanocups based on multiple macrocyclic clusters have been made, showing the fusion of two areas of metallacalixarene and PONb chemistry. The two molecular nanocups are by far the largest two inorganic–organic hybrid PONbs and hold promise for developing largely unexplored inorganic–organic hybrid PONb chemistry.
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