Utilizing supramolecular synthetic macrocycles with distinct porous structures and abundant functional groups as a precursor for metal‐doped carbon electrocatalysts can endow the resulting materials ...with great potential in electrocatalysis. Herein, iridium‐doped electrocatalysts (CBC‐Ir), using a synthetic macrocycle named cucurbit6uril as the carbon source precursor, are designed and prepared. Interestingly, owing to the numerous N‐containing backbone and unique porous structure from cucurbit6uril self‐assembly, the newly designed catalysts CBC‐Ir possess abundant N‐doped and mesoporous structures without the need of additional N sources and templates. The catalysts exhibit superior catalytic performance toward the hydrogen evolution reaction with high Faradaic efficiency (91.5% and 92.7%), superior turnover frequency (2.1 and 0.69 H2 s−1) at the 50 mV overpotential, and only 17 and 33 mV overpotentials in acidic and alkaline conditions reaching the current density of 10 mA cm−2, better than the commercial Pt/C (28 and 43 mV). This work not only expands the application of supramolecular macrocycles in the water splitting field but also provides a new approach for preparing robust electrocatalysts.
Supramolecular macrocycle cucurbit6uril is employed as a carbon source precursor to prepare a series of iridium‐doped N‐rich mesoporous carbon electrocatalysts. The obtained catalysts show ultrahigh electrocatalytic activity for hydrogen evolution reaction both in acidic and alkaline conditions with low overpotentials and high stability.
Noble metal nanoparticles (NMNPs), which spring up like mushrooms, are gaining momentum owing to their unique physicochemical characteristics. Cucurbiturils, a class of synthetic macrocycles with ...intriguing and peculiar host–guest properties, have stimulated tremendous research interest in recent years. The marriage of NMNPs with cucurbiturils is expected to integrate and enhance the excellent characteristics of both components, e.g., precisely controlled particle size, stability, assembly, surface functionality, biocompatibility, tunable optical properties, and high catalytic activities. This review systematically outlines the recent progress on the fabricating strategies and important applications of cucurbiturils‐mediated NMNPs in sensing, surface‐enhanced Raman scattering, theranostics, and catalysis. A brief outlook on the future development of cucurbiturils‐mediated NMNPs is also presented.
Cucurbiturils not only endow noble metal nanoparticles (NMNPs) with exciting new and outstanding properties, but also significantly improve their original performance. The fabricating strategies of cucurbiturils‐mediated NMNPs for sensing, surface‐enhanced Raman scattering, theranostics, and catalysis are thoroughly overviewed, and the development prospects and challenges of cucurbiturils‐mediated NMNPs are also discussed.
We propose a compact planar ultrawideband (UWB) antenna with 3.4/5.5 GHz dual band-notched characteristics. The antenna consists of a beveled rectangular metal patch and a 50 Omega coplanar waveguide ...(CPW) transmission line. By etching two nested C-shaped slots in the patch, band-rejected filtering properties in the WiMAX/WLAN bands are achieved. The proposed antenna is successfully simulated, designed, and measured showing broadband matched impedance, stable radiation patterns and constant gain. An equivalent circuit model of the proposed antenna is presented to discuss the mechanism of the dual band-notched UWB antenna. A UWB antenna and a single band-notched one are also provided for references.
Incorporating synthetic macrocycles with unique structures and distinct conformations into conjugated macrocycle polymers (CMPs) can endow the resulting materials with great potentials in gas uptake ...and pollutant adsorption. Here, four CMPs (CMP‐n, n=1–4) capable of reversibly capturing iodine and efficiently separating carbon dioxide are constructed from per‐triflate functionalized leaning tower6arene (LT6‐OTf) and 2biphenyl‐extended pillar6arene (BpP6‐OTf) via Pd‐catalyzed Sonogashira–Hagihara cross‐coupling reaction. Intriguingly, owing to the appropriate cavity size of LT6‐OTf and the numerous aromatic rings in the framework, the newly designed CMP‐4 possesses an outstanding I2 affinity with a large uptake capacity of 208 wt % in vapor and a great removal efficiency of 94 % in aqueous solutions. To our surprise, with no capacity to accommodate nitrogen, CMP‐2 constructed from BpP6‐OTf is able to specifically capture carbon dioxide at ambient conditions.
Four catcher‐type conjugated macrocycle polymers (CMP‐n, n=1–4) have been designed and synthesized successfully, exhibiting interesting application in CO2 and I2 uptake. The CMP‐2 is able to capture CO2 with excellent selectivity and the CMP‐4 is capable of adsorbing iodine with outstanding capacity.
Cancer poses a significant challenge to global public health, seriously threatening human health and life. Although various therapeutic strategies, such as chemotherapy (CT), radiotherapy, ...phototherapy, and starvation therapy, are applied to cancer treatment, their limited therapeutic effect, severe side effects, and unsatisfactory drug release behavior need to be carefully considered. Thus, there is an urgent need to develop efficient drug delivery strategies for improving cancer treatment efficacy and realizing on‐demand drug delivery. Notably, pillararenes, as an emerging class of supramolecular macrocycles, possess unique properties of highly tunable structures, superior host–guest chemistry, facile modification, and good biocompatibility, which are widely used in cancer therapy to achieve controllable drug release and reduce the toxic side effects on normal tissues under various internal/external stimuli conditions. This review summarizes the recent advance of stimuli‐responsive supramolecular delivery systems (SDSs) based on pillararenes for tumor therapy from the perspectives of different assembly methods and hybrid materials, including molecular‐scale SDSs, supramolecular nano self‐assembly delivery systems, and nanohybrid SDSs. Moreover, the prospects and critical challenges of stimuli‐responsive SDSs based on pillararenes for cancer therapy are also discussed.
The recent advancements and application prospects of stimuli‐responsive supramolecular delivery systems (SDSs) based on pillararenes, including molecular‐scale SDSs, supramolecular nano self‐assembly, and nanohybrid SDSs for cancer therapy, are highlighted, and the development prospects and challenges of pillararene‐based SDSs for cancer therapy are also discussed.
Supramolecular polymers have attracted increasing attention in recent years due to their perfect combination of supramolecular chemistry and traditional polymer chemistry. The design and synthesis of ...macrocycles have driven the rapid development of supramolecular chemistry and polymer science. Pillarnarenes, a new generation of macrocyclic compounds possessing unique pillar‐shaped structures, nano‐sized cavities, multi‐functionalized groups, and excellent host–guest complexation abilities, are promising candidates to construct supramolecular polymer materials with enhanced properties and functionalities. This review summarizes recent progress in the design and synthesis of pillararene‐based supramolecular polymers (PSPs) and illustrates their diverse applications as adsorption and separation materials. All performances are evaluated and analyzed in terms of efficiency, selectivity, and recyclability. Typically, PSPs can be categorized into three typical types according to their topologies, including linear, cross‐linked, and hybrid structures. The advances made in the area of functional supramolecular polymeric adsorbents formed by new pillararene derivatives are also described in detail. Finally, the remaining challenges and future perspectives of PSPs for separation‐based materials science are discussed. This review will inspire researchers in different fields and stimulate creative designs of supramolecular polymeric materials based on pillararenes and other macrocycles for effective adsorption and separation of a variety of targets.
Supramolecular polymer materials have attracted significant attention for wide potential applications in numerous fields, particularly in adsorption and separation, due to the elegant combination of supramolecular chemistry with polymer science. This review highlights the recent advancements in pillararene‐based supramolecular polymers for adsorption and separation applications, with an emphasis on their synthetic strategies, adsorption mechanisms, and separation performances.
SUMMARY
Fruit ripening is a complex developmental process, which is modulated by both transcriptional and post‐translational events. Control of fruit ripening is important in maintaining moderate ...quality traits and minimizing postharvest deterioration. In this study, we discovered that the transcription factor MaMYB4 acts as a negative regulator of fruit ripening in banana. The protein levels of MaMYB4 decreased gradually with banana fruit ripening, paralleling ethylene production, and decline in firmness. DNA affinity purification sequencing combined with RNA‐sequencing analyses showed that MaMYB4 preferentially binds to the promoters of various ripening‐associated genes including ethylene biosynthetic and cell wall modifying genes. Furthermore, ectopic expression of MaMYB4 in tomato delayed tomato fruit ripening, which was accompanied by downregulation of ethylene biosynthetic and cell wall modifying genes. Importantly, two RING finger E3 ligases MaBRG2/3, whose protein accumulation increased progressively with fruit ripening, were found to interact with and ubiquitinate MaMYB4, contributing to decreased accumulation of MaMYB4 during fruit ripening. Transient overexpression of MaMYB4 and MaBRG2/3 in banana fruit ripening delayed or promoted fruit ripening by inhibiting or stimulating ethylene biosynthesis, respectively. Taken together, we demonstrate that MaMYB4 negatively modulates banana fruit ripening, and that MaMYB4 abundance could be regulated by protein ubiquitination, thus providing insights into the role of MaMYB4 in controlling fruit ripening at both transcriptional and post‐translational levels.
Significance Statement
MaMYB4 negatively modulates banana fruit ripening by specifically targeting a subset of ripening‐associated genes and it could be regulated by MaBRG2/3‐mediated ubiquitination.
An intelligent theranostic nanoplatform based on nanovalve operated metal–organic framework (MOF) core–shell hybrids, incorporating tumorous microenvironment‐triggered drug release, magnetic ...resonance imaging (MRI) guidance, sustained release, and effective chemotherapy in one pot is reported. The core–shell hybrids are constructed by an in situ growth method, in which Fe3O4 particles with superior abilities of MRI and magnetic separation form the core and UiO‐66 MOF with high loading capacity compose the shell, and then are surface‐installed with pillararene‐based pseudorotaxanes as tightness‐adjustable nanovalves. This strategy endows the system with the ability of targeted, multistimuli responsive drug release in response to pH changes, temperature variations, and competitive agents. Water‐soluble carboxylatopillar6arene system achieved sustained drug release over 7 days due to stronger host–guest binding, suggesting that the nanovalve tightness further reinforces the desirable release of anticancer agent over a prolonged time at the lesion site.
A theranostic nanoplatform based on a water‐soluble pillararene gated magnetic core–shell metal–organic framework (MOF) is fabricated, incorporating high drug loading capacity, multistimuli responsive drug release, sustained drug release, magnetic resonance imaging synergistic diagnosis, and effective chemotherapy in one pot. Such a facile strategy provides a promising perspective for the construction of a multifunctional MOF‐based theranostic nanoplatform.
Tailoring the properties of solid‐state organic luminescent materials using a bottom‐up design principle is highly desirable for many applications. Herein, we present a “macrocycle‐to‐framework” ...strategy to construct macrocycle‐functionalized and hydrazone‐linked functional organic polymers with bright yellowish‐green luminescence and unique solvatochromism behaviors by the condensation of a diacylhydrazine‐functionalized pillar5arene with tris(4‐formylbiphenyl)amine. Outperforming their non‐macrocycle‐incorporated counterparts, the pillar5arene‐containing materials display amplified sensitivity to acidic conditions with luminescent and colorimetric dual‐modal patterns assisted by the enhanced intramolecular charge transfer (ICT), and exhibit satisfactory responsiveness to nitrobenzene compounds through rapid luminescence quenching with high selectivity and a low detection limit, where the sensing process proceeds through multiple dynamic quenching pathways.
A brightly emissive hydrazone‐linked covalent polymer platform based on pillar5arene‐derived building blocks has been developed for the optical sensing of acidic pH levels as well as nitroaromatic compounds. The macrocyclic acceptors play important roles in improving the sensing sensitivity and durability, thus providing valuable insight for the construction of versatile molecular platforms with innovative structures and designable functions.
The role of noninvasive liver fibrosis markers which were developed to evaluate the severity of chronic liver disease remains unclear in cirrhosis.
To evaluate the correlation between noninvasive ...markers and hemodynamic parameters and their prognostic performance in cirrhotic patients.
A total of 242 cirrhotic patients undergoing hemodynamic study were analyzed. The correlations between noninvasive models, including FIB-4, aspartate aminotransferase to platelet ratio index, cirrhosis discriminant score, Lok index, Goteborg University Cirrhosis Index, and albumin-bilirubin (ALBI) score and hemodynamic parameters were investigated, along with their predictive accuracy for short- and long-term survival.
There was a significant correlation between all noninvasive markers and hepatic venous pressure gradient (HVPG), and ALBI score had the best correlation (r = 0.307, p<0.001). For the prediction of 3-month and 6-month mortality, serum sodium (sNa) levels had the highest area under curve (AUC; 0.799 and 0.818, respectively) among all parameters, and ALBI score showed the best performance (AUC = 0.691 and 0.740, respectively) compared with other 5 noninvasive models. Of 159 patients with low MELD scores (<14), high ALBI score (>-1.4) and low sNa (<135 mmol/L) predicted early mortality. In the Cox multivariate model, ALBI, MELD, HVPG and sNa were independent predictors of long-term survival.
Among noninvasive markers, ALBI score is best correlated with HVPG and associated with short-term outcome in cirrhotic patients. A high ALBI score and low sNa identify high-risk patients with low MELD scores. High MELD, HVPG, ALBI and low sNa levels are independent predictors of survival. Independent studies are required to confirm our findings.
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