Crystalline and porous covalent organic frameworks (COFs) and metal‐organic frameworks (MOFs) materials have attracted enormous attention in the field of photocatalytic H2 evolution due to their ...long‐range order structures, large surface areas, outstanding visible light absorbance, and tunable band gaps. In this work, we successfully integrated two‐dimensional (2D) COF with stable MOF. By covalently anchoring NH2‐UiO‐66 onto the surface of TpPa‐1‐COF, a new type of MOF/COF hybrid materials with high surface area, porous framework, and high crystallinity was synthesized. The resulting hierarchical porous hybrid materials show efficient photocatalytic H2 evolution under visible light irradiation. Especially, NH2‐UiO‐66/TpPa‐1‐COF (4:6) exhibits the maximum photocatalytic H2 evolution rate of 23.41 mmol g−1 h−1 (with the TOF of 402.36 h−1), which is approximately 20 times higher than that of the parent TpPa‐1‐COF and the best performance photocatalyst for H2 evolution among various MOF‐ and COF‐based photocatalysts.
Effective separation: A novel MOF/COF hybrid material assembled by covalent connecting two components, exhibits effective visible‐light‐driven photocatalytic H2 evolution due to the ideal band matching and effectively promoting the separation of the photogenerated charges and holes.
Abstract
The design of highly stable, selective and efficient electrocatalysts for CO
2
reduction reaction is desirable while largely unmet. In this work, a series of precisely designed ...polyoxometalate-metalloporphyrin organic frameworks are developed. Noted that the integration of {ε-PMo
8
V
Mo
4
VI
O
40
Zn
4
} cluster and metalloporphyrin endows these polyoxometalate-metalloporphyrin organic frameworks greatly advantages in terms of electron collecting and donating, electron migration and electrocatalytic active component in the CO
2
reduction reaction. Thus-obtained catalysts finally present excellent performances and the mechanisms of catalysis processes are discussed and revealed by density functional theory calculations. Most importantly, Co-PMOF exhibits remarkable faradaic efficiency ( > 94%) over a wide potential range (−0.8 to −1.0 V). Its best faradaic efficiency can reach up to 99% (highest in reported metal-organic frameworks) and it exhibits a high turnover frequency of 1656 h
−1
and excellent catalysis stability ( > 36 h).
ABSTRACT
Purpose
To investigate the effects of the particle size and surface coating on the cellular uptake of the polymeric nanoparticles for drug delivery across the physiological drug barrier with ...emphasis on the gastrointestinal (GI) barrier for oral chemotherapy and the blood–brain barrier (BBB) for imaging and therapy of brain cancer.
Methods
Various sizes of commercial fluorescent polystyrene nanoparticles (PS NPs) (
viz
20 50, 100, 200 and 500 nm) were modified with the d-α-tocopheryl polyethylene glycol 1,000 succinate (vitamin E TPGS or TPGS). The size, surface charge and surface morphology of PS NPs before and after TPGS modification were characterized. The Caco-2 and MDCK cells were employed as an
in vitro
model of the GI barrier for oral and the BBB for drug delivery into the central nerve system respectively. The distribution of fluorescent NPs after
i.v.
administration to rats was analyzed by the high performance liquid chromatography (HPLC).
Results
The
in vitro
investigation showed enhanced cellular uptake efficiency for PS NPs in both of Caco-2 and MDCK cells after TPGS surface coating.
In vivo
investigation showed that the particle size and surface coating are the two parameters which can dramatically influence the NPs biodistribution after
intravenous
administration. The TPGS coated NPs of smaller size (< 200 nm) can escape from recognition by the reticuloendothelial system (RES) and thus prolong the half-life of the NPs in the blood system.
Conclusions
TPGS-coated PS NPs of 100 and 200 nm sizes have potential to deliver the drug across the GI barrier and the BBB.
CaO-biochar composites were prepared by mixed ball milling and pyrolysis of agricultural wastes eggshell and rice straw. The resulting CaO-biochar composites (E-C) showed excellent performance for ...phosphate adsorption from aqueous solution in a wide range of solution pH (5–11), and a maximum adsorption capacity of 231 mg/g could be obtained by E-C sample that was prepared from the eggshell and rice straw with a mass ratio of 1:1 (E-C 1:1). The adsorption of phosphate onto the E-C samples could be well described by pseudo-second-order (R2 > 0.975) and Langmuir models (R2 > 0.979). Thermodynamic analysis revealed that the adsorption process was spontaneous (ΔG0 < 0) and endothermic (ΔH0 > 0). This work provides a promising method to prepare functionalized biochar adsorbents from agricultural wastes for the recovery of phosphate from aqueous solution, and the phosphate adsorbed CaO-biochar composites can be directly applied as a slow-release fertilizer to farmland soil, which have the functions of improving soil physical structure, increasing soil fertility, and regulating soil pH.
Display omitted
•CaO-biochar composites prepared from agricultural wastes eggshell and rice straw•The composite showed good performance for phosphate adsorption from aqueous solution.•A high adsorption capacity of 231 mg/g for phosphate could be obtained.•The phosphate adsorbed CaO-biochar composite can be used as a slow-release fertilizer.
Abstract d -α-tocopheryl polyethylene glycol succinate (Vitamin E TPGS, or simply TPGS) is a water-soluble derivative of natural Vitamin E, which is formed by esterification of Vitamin E succinate ...with polyethylene glycol (PEG). As such, it has advantages of PEG and Vitamin E in application of various nanocarriers for drug delivery, including extending the half-life of the drug in plasma and enhancing the cellular uptake of the drug. TPGS has an amphiphilic structure of lipophilic alkyl tail and hydrophilic polar head with a hydrophile/lipophile balance (HLB) value of 13.2 and a relatively low critical micelle concentration (CMC) of 0.02% w/w, which make it to be an ideal molecular biomaterial in developing various drug delivery systems, including prodrugs, micelles, liposomes and nanoparticles, which would be able to realize sustained, controlled and targeted drug delivery as well as to overcome multidrug resistance (MDR) and to promote oral drug delivery as an inhibitor of P-glycoprotein (P-gp). In this review, we briefly discuss its physicochemical and pharmaceutical properties and its wide applications in composition of the various nanocarriers for drug delivery, which we call TPGS-based drug delivery systems.
Highlights • This review provides updated epidemiologic data on intrahepatic cholangiocarcinoma. • Various forms of biliary inflammations, as well as many metabolic factors, are identified as risk ...factors of ICC. • We assessed the role of surgical resection and other treatment modalities, as well as their short-term and long-term outcomes.
There has been suggestive evidence of intermediate-mass black holes (IMBHs; 103−5 M ) existing in some globular clusters (GCs) and dwarf galaxies, but IMBHs as a population remain elusive. As a ...main-sequence star passes too close by an IMBH it might be tidally captured and disrupted. We study the long-term accretion and observational consequence of such tidal disruption events. The disruption radius is hundreds to thousands of the BH's Schwarzschild radius, so the circularization of the falling-back debris stream is very inefficient due to weak general relativity effects. Due to this and a high mass fallback rate, the bound debris initially goes through a ∼10 yr long super-Eddington accretion phase. The photospheric emission of the outflow ejected during this phase dominates the observable radiation and peaks in the UV/optical bands with a luminosity of . After the accretion rate drops below the Eddington rate, the bolometric luminosity follows the conventional t−5/3 power-law decay, and X-rays from the inner accretion disk start to be seen. Modeling the newly reported IMBH tidal disruption event candidate 3XMM J2150-0551, we find a general consistency between the data and predictions. The search for these luminous, long-term events in GCs and nearby dwarf galaxies could unveil the IMBH population.
Great efforts have been devoted so far to combine nano‐magnetic hyperthermia and nano‐photothermal therapy to achieve encouraging additive therapeutic performance in vitro and in vivo with limitation ...to direct intratumoral injection and no guidance of multimodality molecular imaging. In this study, a novel multifunctional theranostic nanoplatform (MNP@PES‐Cy7/2‐DG) consisting of magnetic nanoparticles (MNPs), poly(3,4‐ethylenedioxythiophene):poly(4‐styrenesulfonate) (PES), Cyanine7 (Cy7), and 2‐deoxyglucose (2‐DG)‐polyethylene glycol is developed. They are then applied to combined photo‐magnetic hyperthermia therapy under intravenous administration that is simultaneously guided by trimodality molecular imaging. Remarkably, nanoparticles are found aggregated mainly in the cytoplasm of tumor cells in vitro and in vivo, and exhibit stealth‐like behavior with a long second‐phase blood circulation half‐life of 20.38 ± 4.18 h. Under the guidance of photoacoustic/near‐infrared fluorescence/magnetic resonance trimodality imaging, tumors can be completely eliminated under intracellular photo‐magnetic hyperthermia therapy with additive therapeutic effect due to precise hyperthermia. This study may promote a further exploration of such a platform for clinical applications.
A novel multifunctional theranostic nanoplatform (MNP@PES‐Cy7/2‐DG) is developed and applied for combined photo‐magnetic hyperthermia therapy under intravenous administration, which is simultaneously guided by multimodality molecular imaging. Under the guidance of photoacoustic imaging/magnetic resonance imaging/fluorescence molecular imaging tumors can be completely eliminated under intracellular inside‐out hyperthermia with additive therapeutic effect due to precise hyperthermia.
Baicalin is reported as an effective drug for ulcerative colitis (UC). However, its effect on gut microbiota and short-chain fatty acids (SCFAs) remains unknown. In this study, we investigated the ...role of baicalin on Th17/Treg balance, gut microbiota community, and SCFAs levels in trinitrobenzene sulphonic acid (TNBS)-induced UC rat model. We found the DAI scores were significantly increased in the TNBS-treated rats, while reduced in the baicalin-treated group in a dose-dependent manner, accompanied with the alleviation of mucosal injury, the reduction of ZO-1, Occludin, and MUC2 expression. At the meanwhile, baicalin repressed the increased levels of reactive oxygen species (ROS) and MDA, while deceased the GSH and SOD levels in colon tissue of rats treated with TNBS. On the other hand, administration of baicalin attenuated the TNBS-induced upregulations of Th17/Treg ratio, indicating a strong amelioration in the colorectal inflammation. More importantly, pyrosequencing of the V4 regions of 16S rRNA genes in rat feces revealed a deviation of the gut microbiota in response to baicalin treatment. In particular, the decreased
Firmicutes
-to-
Bacteroidetes
ratios and endotoxin-bearing
Proteobacteria
levels indicated that baicalin reversed TNBS-induced gut dysbiosis OTUs. In addition, we further investigated the fecal levels of major SCFAs in rats and found that baicalin significantly resorted the fecal butyrate levels in rats treated with TNBS. The increased butyrate levels were in consistent with the higher abundance of butyrate-producing species such as
Butyricimonas
spp.,
Roseburia
spp.,
Subdoligranulum
spp., and
Eubacteriu
spp. in baicalin-treated group. In conclusion, our findings suggest that baicalin possibly protected rats against ulcerative colitis by regulation of Th17/Treg balance, and modulation of both gut microbiota and SCFAs. Baicalin may be used as a prebiotic agent to treat ulcerative colitis-associated inflammation and gut dysbiosis.
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