A two‐stage mediated near‐infrared (NIR) emissive supramolecular assembly for lysosome‐targeted cell imaging is presented. 4,4′‐Anthracene‐9,10‐diylbis(ethene‐2,1‐diyl))bis(1‐ethylpyridin‐1‐ium) ...bromide (ENDT) was synthesized as an organic dye with weak fluorescence emission at 625 nm. When ENDT complexes with cucurbit8uril (CB8), this binary supramolecular complex assembles into nanorods with a near‐infrared fluorescence emission (655 nm) and fluorescence enhancement as the first stage. Such supramolecular complexes interact with lower‐rim dodecyl‐modified sulfonatocalix4arene (SC4AD) to form nanoparticles for further fluorescence enhancement as the second stage. Furthermore, based on a co‐staining experiment with LysoTracker Blue, such nanoparticles can be applied in NIR lysosome‐targeted cell imaging.
Supramolecular assemblies were designed with initially weak 625 nm near‐IR emission that was enhanced and shifted to 655 nm in two stages by cucurbit8uril (CB8) and amphiphilic calixarene SC4AD. This system was used for lysosome‐targeted cell imaging.
Calixarene is the third generation of supra-molecular compounds after crown ether and cyclodextrin. Amphiphilic calixarene can be obtained by modulation with both hydrophilic group and hydrophobic ...alkyl chain. Compared with conventional surfactant, amphiphilic calixarene has much lower critical micelle concentration and is much easier to self-assemble into different morphological aggregates. Calixarene-basedsupra-amphiphile can be designed via noncovalent bonds due to the capability of calixarene to recognize surfactant; the binding of a surfactant with calixarene can decrease the critical micelle concentration of surfactant by several times. The calixarene-surfactant complex can self-aggregate to form spherical micelles, vesicles, and spherical nanoparticles, and the aggregation behavior can be controlled by the structures and the molar ratio of surfactant to calixarene and environmental factors. Calixarene-based amphiphile and supra-amphiphile show low cytotoxicity. They can load drugs and assemble into nanocapsules with drugs. The structure of the calixarene-drug complex can respond to external stimuli, rendering the sustained release of the drug and suggesting its potential application as a drug delivery system. Recently, calixarene has also been found to selectively bind proteins, suggesting its prospect in disease diagnosis and intervention treatment in clinics. This review elaborates on the research progress in the self-assembly behaviors of calixarene-based amphiphile and supra-amphiphile and the applications of the calixarenes in drug delivery and protein recognition. The prospectives for the studies are also provided in this review.
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•Calixarene can be functionalized to form calixarene-based amphiphile.•Calixarene can bind with surfactant to form supra-amphiphile.•Calixarene-based amphiphile and supra-amphiphile can form different assemblies.•Calixarene can load drug and release drug in a sustainedway.•Calixarene can selectively bind protein and disturb protein-protein interaction.
Covalent Organic Frameworks
In article number 2304989, Lei‐Lei Liu, Zhongyue Li, and co‐workers synthesize a calix4arene‐derived covalent organic framework (COF)‐C4A‐benzothiadiazole (BTD), which ...exhibits high crystallinity and features a non‐interpenetrating undulating 2D layered structure with AA‐stacking. COF‐C4A‐BTD has an appropriate electron donor‐acceptor and energy band structures which can facilitate the generation and separation of ·O2− and h+, resulting in efficient visible‐light‐driven activity for degrading Bisphenol A, Rhodamine B, and Methylene blue.
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•An electrochemical sensor for SARS-CoV-2 was constructed based on a smartphone.•The signal amplification of the sensor was based on supersandwich-type recognition strategy.•The ...detectable ratios of the sensor were higher than those obtained by RT-qPCR.•The sensor has the lowest limit of detection among the published approaches to date.•The sensor showed high specificity and selectivity.
The recent pandemic outbreak of COVID-19 caused by a novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), poses a threat to public health globally. Thus, developing a rapid, accurate, and easy-to-implement diagnostic system for SARS-CoV-2 is crucial for controlling infection sources and monitoring illness progression. Here, we reported an ultrasensitive electrochemical detection technology using calixarene functionalized graphene oxide for targeting RNA of SARS-CoV-2. Based on a supersandwich-type recognition strategy, the technology was confirmed to practicably detect the RNA of SARS-CoV-2 without nucleic acid amplification and reverse-transcription by using a portable electrochemical smartphone. The biosensor showed high specificity and selectivity during in silico analysis and actual testing. A total of 88 RNA extracts from 25 SARS-CoV-2-confirmed patients and eight recovery patients were detected using the biosensor. The detectable ratios (85.5 % and 46.2 %) were higher than those obtained using RT-qPCR (56.5 % and 7.7 %). The limit of detection (LOD) of the clinical specimen was 200 copies/mL, which is the lowest LOD among the published RNA measurement of SARS-CoV-2 to date. Additionally, only two copies (10 μL) of SARS-CoV-2 were required for per assay. Therefore, we developed an ultrasensitive, accurate, and convenient assay for SARS-CoV-2 detection, providing a potential method for point-of-care testing.
Calixarenes, with potential functionalization on the upper and lower rim, have been explored in recent years for the design and construction of anticancer agents in the field of drugs and ...pharmaceuticals. Herein, optimization of bis N-(2-hydroxyethyl) aminocarbonylmethoxyl substituted calix 4 arene (CLX-4) using structure-based drug design and traditional medicinal chemistry led to the discovery of series of calix 4arene carbonyl amide derivatives 5a-5t. Evaluation of the cytotoxicity of 5a-5t employing MTT assay in MCF-7, MDA-MB-231 (human breast cancer cells), HT29 (human colon carcinoma cells), HepG2 (human hepatocellular carcinoma cells), A549 (human lung adenocarcinoma cells) and HUVEC (Human Umbilical Vein Endothelial) cells demonstrated that the most promising compound 5h displayed the most superior inhibitory effect against A549 and MDA-MB-231 cells, which were 3.2 times and 6.8 times of CLX-4, respectively. In addition, the cell inhibition rate (at 10 μM) against normal HUVEC cells in vitro was only 9.6%, indicating the safty of compound 5h. Moreover, compound 5h could inhibit the migration of MDA-MB-231 cell in wound healing assay. Further mechanism studies significantly indicated that compound 5h could block MDA-MB-231 cell cycle arrest in G0/G1 phase by down regulating cyclin D1 and CDK4, and induce apoptosis by up-regulation of Bax, down-regulation of Caspase-3, PARP and Bcl-2 proteins, resulting in the reduction of DNA synthesis and cell division arrest. This work provides worthy of further exploration for the promising calixarene-based anticancer drugs.
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•Novel calix 4arene derivatives were designed and synthesized.•Cell viability assay was evaluated in five selected tumor cells.•The promising compound 5h could inhibit the migration of MDA-MB-231 cell in wound healing assay.•Compound 5h could block MDA-MB-231 cell cycle arrest and induce apoptosis.
Combination therapy based on molecular drugs and therapeutic genes provides an effective strategy for malignant tumor treatment. However, effective gene and drug combinations for cancer treatment are ...limited by the widespread antagonism between therapeutic genes and molecular drugs. Herein, a calixarene‐embedded nanoparticle (CENP) is developed to co‐deliver molecular drugs and therapeutic genes without compromising their biological functions, thereby achieving interference‐free gene–drug combination cancer therapy. CENP is composed of a cationic polyplex core and an acid‐responsive polymer shell, allowing CENP loading and delivering therapeutic genes with improved circulation stability and enhanced tumor accumulation. Moreover, the introduction of carboxylated azocalix4arene, which is a hypoxia‐responsive calixarene derivatives, in the polyplex core endows CENP with the capability to load molecular drugs through the host–guest complexation as well as inhibit the interference between the drugs and genes by encapsulating the drugs into its cavity. By loading doxorubicin and a plasmid DNA‐based CRISPR interference system that targets miR‐21, CENP exhibits the significantly enhanced anti‐tumor effects in mice. Considering the wide variety of calixarene derivatives, CENP can be adapted to deliver almost any combination of drugs and genes, providing the potential as a universal platform for the development of interference‐free gene–drug combination cancer therapy.
In this study, a calixarene‐embedded nanoparticle (CENP) is reported as a universal nanoplatform that can co‐delivermolecular drugs and therapeutic geneswithout compromising their biological functions, thereby achieving interference free gene–drug combination cancer therapy. By loading doxorubicin and a CRISPR interference system that targets miR‐21, CENP exhibits the significantly enhanced anti‐tumor effects in mice.
The limited optical adsorption range and rapid recombination of photoexcited electron-hole pairs have severely hindered the development of ZnO-based photocatalysts. As macromolecular compounds, ...calixarenes become potential photocatalyst modifiers owing to their special molecular structures. In this work, ZnFe2O4/ZnO heterojunction photocatalysts which consist of ZnFe2O4 nanoparticles and ZnO nanosheets were fabricated by simple hydrothermal reaction with the introduction of tetrasulfonatomethyl-n-hexyl calix4resorcinarene tetrasodium (THCRT1). The synthesized ZnFe2O4/ZnO nanocomposite possesses a larger specific surface area, broader-spectrum absorption and an electronegative surface due to the addition of THCRT. Furthermore, the successful construction of ZnFe2O4/ZnO heterojunction leads to low charge transfer resistance and enhanced photocurrent density. Therefore, the THCRT-capped ZnFe2O4/ZnO composite exhibited superior adsorptive performance and removal efficiency towards Rhodamine B (RhB) and Levofloxacin hydrochloride (LH). The calcined nanocomposite degraded 95.80 % of RhB (10 mg L−1) and 97.86 % of LH (20 mg L−1) after 120 min under simulated sunlight illumination at a minimal catalyst dosage of 0.1 g L−1. Additionally, to determine the band structures, the band gaps, valence band positions and the Fermi levels were measured by Tauc plot, valence band x-ray photoelectron spectroscopy (XPS-Vb) and Mott-Schottky plot, respectively. Finally, based on the band structure results, we proposed a potential photocatalytic mechanism of n-n heterojunction. This work offers a promising prospect in the treatment of sewage containing organic contaminants.
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•ZnFe2O4/ZnO composite was facilely obtained by introduction of sulfonate calixarene.•The calixarene expands the light absorption range of synthesized composite.•The composite processes a large specific surface area and abundant pore structure.•Electronegativity leads to good adsorption capacity towards cationic pollutants.•The composite shows good activity and stability for photodegradation of RhB and LH.
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•Coordination Polymers based on calixarene macrocyclic backbones are reviewed.•Chemical modifications of the lower and upper rim of calixarenes are detailed.•The coordination ...abilities of calixarene based ligands towards metals are presented.•The useful properties of the resulting architectures are highlighted.
The solid-state structures of 1D–3D Coordination Polymers based on the macrocyclic calixarene backbone have been reviewed, based on the chemical nature of appended substituents on the macrocycle platform. The coordination propensity of this class of ligands is analysed, taking into account the different coordinating atoms/groups that can be located on the macrocyclic ligand: (1) the unmodified inherently coordinating thiacalix4arene with the S bridges as donor atoms; (2) different conformations of calixnarene units, with appended O donor atoms; (3) the chemical modification of the upper rim of calixnarenes and thiacalixnarenes, with coordinating groups, in particular the use of the sulfonate groups; (4) calix4arenes, thiacalix4arenes and tetramercaptothiacalix4rene that have been modified at their lower rim (mono, di and tetra substitution) with coordinating groups like cyano, carboxylate, pyridyl and pyrazolyl groups. All the formed coordination networks have been described. A special attention has been drawn to the structural and functional properties of these extended networks: magnetic, luminescence, adsorption and catalytic properties. Perspectives and future challenges in this emerging field are also discussed.
This article looks at the chemistry surrounding the concept of inherently chiral calixarenes (ICCs), whose synthesis and application have only recently being realised. One challenge in the area of ...ICC chemistry is the sheer breadth and scope for installing different aspects of inherent chirality. The aim of this article is not to cover every known method, but rather to give the reader an overview of the main themes that have emerged in this area, including more recent additions to the literature. This overview will also touch on the very limited reports on the applications of ICCs which give a glimpse into the potential these compounds may have in future studies.
Going chiral: This concept article looks at the chemistry surrounding inherently chiral calixarenes (ICCs), the synthesis and applications of which have only recently been realised.
Neutral and efficient: A neutral guest with a cyano site and a triazole site, which can be easily prepared and modified, is demonstrated to strongly bind with pillar5arene (see figure). Based on this ...new recognition motif, two neutral supramolecular polymers in organic media, which are currently unfeasible by means of host–guest interactions of crown ethers and calixarenes, were fabricated. One is AA/BB‐type, and the other is A2/B3‐type.