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Lentinan is a natural β–glucan with various bioactivities and is combined with chemotherapy drugs for cancer treatment. Regorafenib is an oral multi-kinase inhibitor approved by FDA for treatment of metastatic colorectal cancer, advanced hepatocellular carcinoma, and metastatic gastrointestinal stromal tumors. Regorafenib has poor water solubility and multiple toxicities. We report drug–drug nanosuspensions of regorafenib and lentinan. Results of dynamic light scattering and scanning electron microscopy showed that the mean particle size of the regorafenib–lentinan nanosuspensions was approximately 200 nm and was uniformly distributed. Transmission electron microscopy findings indicated that lentinan stabilized the nanosuspensions by steric manner. Hydrogen bonds and hydrophobic interactions were found between regorafenib and lentinan by molecular dynamics simulation. The results of cytotoxicity assay and pharmacokinetics study in rats showed that the regorafenib–lentinan nanosuspensions reduced the toxicity and enhanced the in vitro anticancer activity and oral bioavailability of regorafenib. Lentinan as a natural stabilizer has the potential using for drug nanosuspensions. Drug–drug nanosuspensions are a new form of combination therapies that can reduce the number of drugs taken by patients and improve their compliance.

Melanoma is one of the most common malignant tumors. The anti-PD-1 antibody is used for the treatment of metastatic melanoma. Treatment success is only 35–40% and a range of immune-related adverse reactions can occur. Combination of anti-PD1 antibody therapy with other oncology therapies has been attempted. Herein, we assessed whether chlorogenic acid liposomes modified with sialic acid (CA-SAL) combined with anti-PD1 antibody treatment was efficacious as immunotherapy for melanoma. CA-SAL liposomes were prepared and characterized. In a mouse model of B16F10 tumor, mice were treated with an anti-PD1 antibody, CA-SAL, or combination of CA-SAL + anti-PD1 antibody, and compared with no treatment controls. The tumor inhibition rate, tumor-associated macrophages (TAMs) phenotype, T-cell activity, and safety were investigated. We observed a significant decrease in the proportion of M2-TAMs and CD4+Fop3+ T cells, while there was a significant increase in the proportion of M1-TAMs and CD8+ T cells, and in the activity of T cells, and thus in the tumor inhibition rate. No significant toxicity was observed in major organs. CA-SAL and anti-PD1 Ab combination therapy presented synergistic anti-tumor activity, which enhanced the efficacy of the PD-1 checkpoint blocker in a mouse model of melanoma. In summary, combination immunotherapy of CA-SAL and anti-PD1 Ab has broad prospects in improving the therapeutic effect of melanoma, and may provide a new strategy for clinical treatment., Graphical Abstract

Hemoperfusion has become the third-generation treatment strategy for patients suffering from hyperbilirubinemia, but adsorbents used for bilirubin removal mostly face intractable problems, such as unsatisfactory adsorption performance and poor hemocompatibility. Metal–organic frameworks (MOFs) are promising adsorbents for hemoperfusion due to their high specific surface areas and easily modified organic ligands. However, their microporous properties and separation have hampered their application. Here, a novel hierarchical core–shell nanoplatform (named Double-PEG) with tailored binding sites and pore sizes based on Fe3O4@C and Uio66-NH2 was constructed. Notably, Double-PEG showed excellent bilirubin uptake of up to 1738.30 mg g−1 and maintained excellent bilirubin removal efficiency in simulated biological solutions. A study on the adsorption mechanism showed that the adsorption of Double-PEG towards bilirubin tended to be chemical adsorption and in accordance with the Langmuir model. Besides, the good separability, recyclability, cytotoxicity and hemocompatibility of Double-PEG show great potential in hemoperfusion therapy. The finding of this study may provide a novel insight into the application of MOF materials in the field of hemoperfusion.

Robust nanosheet-assembled Al2O3 (NA-Al2O3) catalysts with a hierarchical hollow microsphere architecture for loading Ni nanoparticles (namely, the Ni/(NA-Al2O3) catalyst) with various Ni loadings (3–20 wt%) were successfully fabricated and used for the dry reforming of methane (DRM). The effect of Ni loadings on the catalytic performance and carbon formation of Ni/(NA-Al2O3) catalysts was studied. The catalysts were characterized by various methods. The results indicate that enhancing the loading of Ni increases the Ni nanoparticle size and initial catalytic activity, and simultaneously declines the nickel dispersion and the interaction between Ni and the carrier. The long-time stability test shows that Ni loading of 5 wt% is considered to be the optimal Ni loading over Ni/(NA-Al2O3) catalysts for the DRM reaction. Further enhancing the Ni loading to 10 or 20 wt% results in almost constant catalytic activity, but increases carbon formation due to the larger nanoparticle size of Ni and the weaker interaction of partial nickel species with the carrier.

The design and synthesis of superhard carbon nitrides have always been a focus of attention. Recently, an experiment has revealed the existence of the previously predicted three-dimensional strongl...

Bismuth-Yttrium Oxide Bi3YO6 (BYO) is well-known among researchers for its potential applications in different fields but its use as an electrode for asymmetric supercapacitor (ASC) has not yet been discussed and uncovered. As high energy and power densities could be well achieved with the aid of optimum potential. In the current scenario, BYO is used as an electrode material for ASCs for the first time. The material is prepared by a solid-state reaction method and its structural, morphological, and electrochemical properties have been explored by using different characterization tools. Structural analysis declared the flourite based structure of BYO having a cubic phase without any visible impurity. In a morphological analysis, a mesoporous thin film with a high surface area (~ 36.6 m2 g−1) with a narrow pore width of (~ 5–18 nm) has been observed. The as-prepared BYO employed as an electrode material for SCs delivers a high specific capacitance of (388 F g−1 at 100 m Vs−1 in the three-electrode system) with excellent cycling stability (5% loss after 6000 cycles). Essentially, an ASC is assembled using BYO and rGO as a positive and negative electrodes operating in a stable and wide potential window up to 2.2 V. Moreover, a high energy density of 11 Wh kg−1 along with a power density of 648 W kg−1 is obtained and maintained a high power density of 888 W kg−1 with the downfall of energy density to 3.7 Wh kg−1. The results prove electrode material as an alternative promising candidate for ASCs.

In this study, a novel carboxymethyl functionalized β-cyclodextrin-modified graphene oxide (CM-β-CD-GO) adsorbent was designed and fabricated. The CM-β-CD-GO was applied to remove methylene blue (MB) from aqueous solutions. The adsorption mechanism was discussed in detail through the study of pH effect, kinetics, and isotherm models. The adsorption of CM-β-CD-GO for MB displayed high removal rates at the pH range of 6.0–10.0, and the removal efficiency is over 90% within 20 minutes. The pseudo-second-order model could well describe the kinetic process of MB adsorption, and the adsorption was determined by the multi-step process. The maximum uptake capability of CM-β-CD-GO towards MB was 245.70 mg g-1 at 25℃according to Langmuir isotherm model. A possible adsorption mechanism that electrostatic attraction, π-π interaction, and host-guest supramolecular interactions supported MB adsorption was proposed. The adsorption capacity of CM-β-CD-GO showed no significant change after five cycles. The structure and morphology of CM-β-CD-GO were characterized by XPS, FT-IR, TGA, PXRD, AFM, SEM, zeta (ζ) potential determination, and Raman spectroscopy. This work provides valuable information for the design of novel adsorbents that specifically and efficiently adsorb cationic dyes contaminants.

传统陶瓷材料的刚性结构变形能力非常有限, 通常在很小的应变下就发生断裂. 具有层状原子结构的陶瓷, 原子层间存在较弱的相互作用, 因而具有大的变形潜力. 我们以氮化硼(BN)为例, 研究了该类陶瓷的室温压缩行为. 分别以洋葱结构BN纳米颗粒和石墨状六方BN纳米片为原料, 采用放电等离子烧结(SPS)技术分别制备了BN-I和BN-II陶瓷材料. 在BN-I中, 随机取向的BN纳米薄片构成三维互锁的结构, 而在BN-II中, BN纳米薄片表现出垂直于SPS压缩方向的择优取向. BN-I的压缩强度为 343 MPa, 断裂应变为4.2%. 相比之下, BN-II的强度和应变分别为 112 MPa 和2.2%. 不同的微观组织结构导致了BN-I和BN-II压缩性能的差异. 此外, 这两种陶瓷材料均表现出1.1%的塑性变形. 该研究表明, 对于具有层状原子结构的陶瓷, 其纳米片作为结构基元构筑成无(或低)择优取向的三维互锁结构, 有望同时提高其强度和变形能力.

Effect of the impurity in Cu2O nanowire on the degradation of methyl orange under light irradiation in dark circumstances was investigated. Here, we present the fabrication of Cu2O nanowires at different temperatures (110, 130, 150, 170, and 190 °C) by a facile hydrothermal route. Meanwhile, at the synthesis temperature of 110–150 °C, the major impurity in Cu2O nanowires was Cu4O3, and a new Cu impurity was introduced in the Cu2O nanowires as the synthesis temperature increased from 170 to 190 °C. Overall, as the synthesis temperature increases from 110 to 190 °C, the total impurity decreases in Cu2O nanowires. The fast degradation rate in dark circumstances has been achieved in Cu2O nanowires for all synthesis temperatures, which can be attributed to the Cu2+ in the Cu4O3 impurity of Cu2O nanowires. This result shows that the Cu2O nanowires obtained at the synthesis temperature of 150 °C have the fastest degradation rate for both under light irradiation and in dark circumstances. It has been found that under light irradiation, the Cu impurity in Cu2O nanowires plays a vital role in the degradation of methyl orange. In the current scenario, different impurity contents influence the catalyst activity of Cu2O nanowires under the visible light or dark, respectively.

Although grafting polymers onto surfaces is widely suggested for designing smart systems, optimizing the performance of such systems is not simple. In this article, we investigate an azo-polymer-based smart surface using the single-chain-in-mean-field theory. Through the numerical simulations, we study the adhesion/erasion transition of the system and show that the performance of the smart surface can be characterized by the difference between the effective nanoparticle–surface interactions in the UV-on and UV-off states. Further exploring the optimization of the smart surface, we find that the distribution function of the receptor can have typical bimodal characteristics, which is crucial for optimizing the position of the azo-bond along the azo-polymer, f. Moreover, the presence of the homopolymer is also essential for the optimal performance of the smart surface, and we build a reference map for the good combinations of f and the homopolymer design fhomo.

The oxygen reduction reaction (ORR), which is a crucial process in fuel cells and metal-air batteries, is currently dominated by Pt-based electrocatalysts. However, these catalysts are expensive and rare on Earth; therefore, these factors are considered to impede the widespread commercialization of these technologies. As a consequence, the development of non-Pt catalysts (such as transition-metal materials) with high performance for ORR has become a main focus of research regarding these renewable energy devices. In the present work, a series of porous triazine-based frameworks (PTFs) co-decorated by iron and iodine have been successfully prepared, using different element doping sequences during the synthesis process. The PTF-Fe-I catalysts shows a high ORR activity in both alkaline and acidic media, with an onset potential of 0.95 V (in basic medium) or 0.85 V (in acidic medium) at a loading of 0.3 mg cm–2. This performance not only exceeds that of the dual-doped counterparts (PTF-I-Fe and PTF-(Fe, I)), ...

Combination therapy including anticancer drugs usually induces synergistic effects, especially in combination with natural compounds as a chemical sensitizer. Nano-based drug delivery technology is also effective in solving the toxicity of single drugs at high doses. In this study, we established a co-delivery strategy for abemaciclib (ABE) combined with vitamin E succinate (VES) based on HA-modified calcium phosphate (CaP) nanomaterials to enhance anti-cancer effect. The nano-sized HA/CaP particles (90 nm) have a hollow structure. Surprisingly, after modification with HA, HA/CaP has more pH sensitivity. CaP released 30% ABE and 91% VES at pH 7.4, whereas HA/CaP vsreleased 14% ABE and 32% VES at the same pH. Cell experiments showed that HA/CaP/ABE-VES had stronger cell inhibitory effect on MCF-7 compared with CaP/ABE-VES. This inorganic/organic composite for the co-delivery of ABE and VES has obvious tumor inhibition effect, and is ideal for anti-tumor drug delivery.

The clinical efficacy of lenvatinib (LFT) is limited by its poor aqueous solubility and low bioavailability. In this work, LFT-loaded soy phospholipid and sodium glycocholate mixed micelles (LFT-MMs) were prepared through classical co-precipitation. And it was served as an oral administration to address these shortcomings. The preparation conditions were optimized by single-factor experiments. The mass ratio of PC, SGC and LFT, and the species of dispersing media were proved to be decisive factors in controlling the properties of LFT-MMs. The optimal LFT-MMs presented prominent enhancement (500-fold) in LFT solubility, high encapsulation efficiency (87.6 %) as well as suitable stability (>1 month at 4 °C). The biocompatibility of LFT-MMs was estimated by in vitro serum stability measurement and hemolysis test. It showed that serum proteins hardly adhered to the surface of LFT-MMs, and insignificant hemolytic rate (

Introduction: At present, there are numerous researches on the migration of components in tablets and granules, however, the investigation in the pharmaceutical literatures concerning the effect of drying rate on the migration of water-soluble components of pellets is limited. Temperature and Relative Humidity (RH) are crucial parameters during the drying process, which is an essential step in the preparation of pellets via wet extrusion/spheronization. To quantify these variables, the water loss percentage of pellets per minute is defined as the drying rate. Aim: The study aimed to investigate the influence of drying rate on the migration of water-soluble components in wet pellets and the potential migrated mechanism. Methods: The pellets containing tartrazine as a water-soluble model drug and microcrystalline cellulose as a matrix former were prepared by extrusion/spheronization and dried at four different drying temperatures and relative humidity. Afterwards, the extent of migrated tartrazine was assessed regarding appearance, in-vitro dissolution test, Differential Scanning Calorimetry, X-Ray Powder Diffraction, Attenuated total reflectance Fourier transform infrared spectroscopy and Confocal Raman Mapping. Results: Results demonstrated that red spots of tartrazine appeared on the surface of pellets and more than 40% tartrazine were burst released within 5 minutes when pellets were dried at 60°C/RH 10%. When pellets were dried at 40°C/RH 80%, none of these aforementioned phenomena were observed. Conclusion: In conclusion, the faster the drying rate was, the more tartrazine migrated to the exterior of pellets. Adjusting drying temperature and relative humidity appropriately could inhibit the migration of water-soluble components within wet extrusion/spheronization pellets.

Pectinases are the emerging enzymes of the biotechnology industry with a 25% share in the worldwide food and beverage enzyme market. These are green and eco-friendly tools of nature and hold a prominent place among the commercially produced enzymes. Pectinases exhibit applications in various industrial bioprocesses, such as clarification of fruit juices and wine, degumming, and retting of plant fibers, extraction of antioxidants and oil, fermentation of tea/coffee, wastewater remediation, modification of pectin-laden agro-industrial waste materials for high-value products biosynthesis, manufacture of cellulose fibres, scouring, bleaching, and size reduction of fabric, cellulosic biomass pretreatment for bioethanol production, etc. Nevertheless, like other enzymes, pectinases also face the challenges of low operational stability, recoverability, and recyclability. To address the above-mentioned problems, enzyme immobilization has become an eminently promising approach to improve their thermal stability and catalytic characteristics. Immobilization facilitates easy recovery and recycling of the biocatalysts multiple times, leading to enhanced performance and commercial feasibility.In this review, we illustrate recent developments on the immobilization of pectinolytic enzymes using polymers and nanostructured materials-based carrier supports to constitute novel biocatalytic systems for industrial exploitability. The first section reviewed the immobilization of pectinases on polymers-based supports (ca-alginate, chitosan, agar-agar, hybrid polymers) as a host matrix to construct robust pectinases-based biocatalytic systems. The second half covers nanostructured supports (nano-silica, magnetic nanostructures, hybrid nanoflowers, dual-responsive polymeric nanocarriers, montmorillonite clay), and cross-linked enzyme aggregates for enzyme immobilization. The biotechnological applications of the resulted immobilized robust pectinases-based biocatalytic systems are also meticulously vetted. Finally, the concluding remarks and future recommendations are also given.

Cerebral ischemia-reperfusion (CIR) can regulate multiple transcription factors to enhance or attenuate injury. Nucleotide-binding oligomerization domain protein 1 (NOD1) has been reported to be involved in autophagy and endoplasmic reticulum (ER) stress. Moreover, autophagy and ER stress play important roles in CIR injury. Hence, the function of NOD1 in CIR injury was explored in this study. Primary rat cortical neurons were treated with oxygen-glucose deprivation and reperfusion (OGD/R) in vitro. NOD1 level was measured using immunofluorescence, real-time quantitative PCR and western blotting and its ubiquitination using co-immunoprecipitation. Results showed that OGD/R up-regulated NOD1 level but inhibited NOD1 ubiquitination. Then the effect of NOD1 on OGD/R-induced changes in cell viability, apoptosis, autophagy and ER stress was evaluated by methyl thiazolyl tetrazolium assay, lactate dehydrogenase release, Hoechst staining, detection of autophagy and ER stress-related proteins using western blotting and infection with GFP-LC3 lentiviruses. OGD/R decreased cell viability and increased cell apoptosis. NOD1 up-regulation promoted these changes, but NOD1 down-regulation reversed these changes. Moreover, OGD/R triggered autophagy and ER stress and NOD1 silencing reversed OGD/R-induced changes in autophagy and ER stress. To validate the role of autophagy in OGD/R injury, autophagy inducer rapamycin was used. Rapamycin promoted OGD/R-induced decrease in cell viability and counteracted NOD1 silencing-induced increase in cell viability. In addition, ER stress inducer tunicamycin was used to investigate the relationship between ER stress and autophagy. Tunicamycin promoted OGD/R-induced decrease in cell viability and reversed NOD1 silencing-induced increase in cell viability. Tunicamycin also enhanced OGD/R-induced autophagy and reversed NOD1 silencing-induced inhibition in autophagy. The results indicated that NOD1 promoted OGD/R injury in cortical neurons through activating ER stress-mediated autophagy. This study provides new insights for the target of CIR injury treatment.

Single-atom electrocatalysts have attracted board interest in the recent years as they combine the advantages of heterogeneous and homogeneous electrocatalysts. Nevertheless, single-atom electrocatalysts with single metal component cannot further satisfy the demand of catalytic properties. This work developed atomic Co/Ni dual sites in N-doped porous carbon Janus-like frameworks through epitaxial growth of cobalt based MOFs on nickel complexes. Structural characterization and atomic-scale transmission electron microscopy revealed the homogeneously dispersed active sites of Co-Ni alloy and single Co/Ni atoms. Electrochemical data strongly demonstrated the advantages of integrating Co-MOF and Ni complex with different topological structures to form a Janus-like structure. The resultant catalysts afforded onset potential of 0.93 V and half-wave potential of 0.84 V for oxygen reduction reaction in alkaline media, and 0.86 V and 0.73 V in acid media, which is better than single noble-metal-free catalysts, even close to commercial Pt/C. Besides, the catalysts also exhibited good oxygen evolution reaction performance (a current density of 10 mA cm−2 at a potential of 1.59 V) and overvoltage between ORR and OER is 0.78 V. Density functional theory calculations indicated the high electrocatalytic activities are originated from the synergetic effect of atomic Co/Ni-N-C bonds and microstructure of the prepared materials. This work paves a new avenue for the development of multiatomic electrocatalysts for energy conversion.

In this study, ionic liquids-based salting-out extraction and sugaring-out extraction were developed to extract succinic acid. Among these five investigated ionic liquids, the ionic liquid with BF4- and OTF− anion showed the ability to form two phases not only with glucose but also with salts. However, the ionic liquid with Br− anion cannot form aqueous two-phase system with glucose, but with salts. Relatively high extractabilities were obtained by ILs–based salting-out extraction systems compared to sugaring-out systems. The extraction efficiency values ranging between 47% and 86% were obtained when succinic acid concentration increased from 5 g/L to 70 g/L in [Bmim]BF4/(NH4)2SO4 systems. It was implied that succinic acid concentration was a key factor in ILs-based salting-out extraction system. Compared to salting-out extraction, sugaring-out extraction was more suitable for succinic acid separation due to the bottom phase reutilization to achieve coupling of fermentation and separation. The distribution behavior of succinic acid in [Bmim]BF4/glucose sugaring-out extraction system depends on not only the concentrations of ionic liquid and glucose, but also the pH. The partition coefficient (2.53) and recovery (75.96%) of succinic acid were obtained by a sugaring-out system consisting of 45% (w/w) [Bmim]BF4 and 30% (w/w) glucose at pH 2.0. Moreover, to support the applicability of ILs-based sugaring-out extraction for SA separation, the most prominent systems were further tested with actual fermentation broth. The extraction efficiencies were 73.71% and 72.53% for filtered and unfiltered fermentation broth, respectively. The remarkable results obtained in this work support the establishment of IL-based sugaring-out extraction as a sound basis of greener cost-effective strategies with a substantial reduction in the environmental footprint and economical issues.

This study aimed to develop a novel sustained release system for mesalazine (MSZ) by preparing hydroxypropyl-β-cyclodextrin (HP-β-CD) inclusion complex loaded chitosan (CS) nanoparticles (NPs). The HP-β-CD/MSZ complex was prepared at 1:1 stoichiometry and characterized by using various analysis techniques. The HP-β-CD/MSZ/CS NPs prepared under the optimum condition had a spherical shape (90±17 nm diameter), a narrow size distribution, and a high loading efficiency. Compared with free MSZ, the HP-β-CD/MSZ/CS NPs exhibited an obvious sustained release of MSZ. The activity of the NPs against a cytokine-triggered inflammatory response was evaluated in cytokine-stimulated HT-29 cell lines by monitoring key inflammatory mediators. The results revealed that compared with free MSZ, the NPs more strongly inhibited the production of NO, PGE2, and IL-8, indicating the NPs possibly had better anti-inflammatory effects. Therefore, the established HP-β-CD/MSZ/CS NPs may be a promising delivery system of MSZ.

The interaction mechanism and binding mode of capecitabine with ctDNA was extensively investigated using docking and molecular dynamics simulations, fluorescence and circular dichroism (CD) spectroscopy, DNA thermal denaturation studies, and viscosity measurements. The possible binding mode and acting forces on the combination between capecitabine and DNA had been predicted through molecular simulation. Results indicated that capecitabine could relatively locate stably in the G-C base-pairs-rich DNA minor groove by hydrogen bond and several weaker nonbonding forces. Fluorescence spectroscopy and fluorescence lifetime measurements confirmed that the quenching was static caused by ground state complex formation. This phenomenon indicated the formation of a complex between capecitabine and ctDNA. Fluorescence data showed that the binding constants of the complex were approximately 2 × 10

Herein, a series of azobenzene (Azo)-containing side-chain cyclic polymers were successfully synthesized by combining atom transfer radical polymerization (ATRP) and Cu(I)-catalyzed azide/alkyne cycloaddition (CuAAc) “click” reaction. The aggregates of linear and cyclic Azo polymers in a dichloroethane/limonene mixed solvent were characterized by circular dichroism (CD) and UV-visible spectroscopy, demonstrating that the topological structural constraint and molecular mass of cyclic polymers have clear effects on the supramolecular chirality driven by a chiral solvent. The difference between linear and cyclic Azo aggregates in supramolecular chirality became less distinct with increasing molecular mass of Azo polymers. The chiroptical switch of cyclic Azo polymers was firstly constructed by trans–cis photoisomerization and cis–trans heating-assisted reorganization processes. These interesting findings suggest that the cyclic topology has a clear influence on the behavior of supramolecular chirality induced by chiral limonene.

The catalytic Staudinger–Vilarrasa (S–V) reaction, a widely utilized reaction for synthesizing amide-containing compounds, has played vital roles in organic synthesis. In this work, we introduce this reaction as a highly efficient chemistry strategy for the first time in polymer chemistry. First, the polycondensation of dicarboxylic acids with organic diazides produces a series of polyamides in yields of up to 94% and high molecular weight of 28 kDa. Second, this reaction between polymer-N3 and various functional organic acids yields amide-end-functionalized polymers with near 100% efficiency. Third, amide-linked (multi)block copolymers (PEG-PEG, PS-PS, PS-b-PEG, PtBA-b-PEG) with approximate 100% efficiency, a star polymer (PEG)3 with ∼95% efficiency and side-chain amide-functionalized polymers (∼100% efficiency) are constructed via this reaction between polymers and organic acids or polymers. This highly efficient catalytic S–V reaction provides a programable platform for producing amide bond-containing polymers that compares favourably with previous reported click strategies, such as CuAAC, thiol–ene and Diels–Alder reactions in some ways.

A cyclic grafted polymer, as a novel and unique kind of polymer, possesses a cyclic backbone and linear grafted side chains. Their physical properties and conformations are controlled by steric hindrance from the grafted side chains. As a cyclic derivative, cyclic grafted polymers have been successfully prepared and characterized within the past decade. To the best of our knowledge, cyclic grafted polymers have not been systematically generalized and summarized. In this review, we illustrate the considerable advances in the architectural construction of cyclic grafted polymers with three different approaches, including “grafting through”, “grafting onto” and “grafting from”. Additionally, their potential applications are also briefly discussed.

A series of carbonaceous-supported precious-metal-free polyoxometalate (POM)-based composites which can be easily synthesized on a large scale was shown to act as efficient cathode materials for the oxygen reduction reaction (ORR) in neutral or basic media via a four-electron mechanism with high durability. Moreover, exploiting the versatility of the considered system, its activity was optimized by the judicious choice of the 3d metals incorporated in the {(PW9)2M7} (M = Co, Ni) POM core, the POM counterions and the support (thermalized triazine-based frameworks (TTFs), fluorine-doped TTF (TTF-F), reduced graphene oxide, or carbon Vulcan XC-72. In particular, for {(PW9)2Ni7}/{Cu(ethylenediamine)2}/TTF-F, the overpotential required to drive the ORR compared well with those of Pt/C. This outstanding ORR electrocatalytic activity is linked with two synergistic effects due to the binary combination of the Cu and Ni centers and the strong interaction between the POM molecules and the porous and highly conducti...

Selective hydrogenation of amino acid methyl esters to chiral amino alcohols is an important and fascinating process. The CuZn0.3Mg0.1AlOx catalyst for the synthesis of chiral amino alcohols was prepared by the fractional co-precipitation method in the 50–100 g scale. The effect of the reduction gas on the catalytic activity, and the effects of the reaction conditions (R-p-m/Cat, temperature, reaction time, H2 pressure and solvent) on the catalytic hydrogenation of R-phenylglycine methyl ester (marked as R-p-m) were investigated. When R-p-m in the ethanol solvent was hydrogenated at 5 MPa of H2 and 80 °C for 10 h over this catalyst reduced by H2, 87.7% yield of R-phenylglycinol with ~ 100% ee value was obtained, and its reaction activation energy (Ea) was 36.7 kJ/mol. After repeated usage 16 times, its catalytic activity was hardly varied. Using this catalyst to catalyze the preparation of other amino alcohols, the high yield of product with ~100% ee value was obtained also.

Proliferative diabetic retinopathy (PDR) is a progressive disease predominantly involving pathological angiogenesis and is characterized by the development of immature, fragile, and easily hemorrhagic new vessels. Advanced glycation end products (AGEs) and the receptor for AGEs (RAGE) play important roles in the progression of diabetic retinopathy. Our previous studies demonstrated that AGEs promoted HUVEC angiogenesis by inducing moesin phosphorylation via RhoA/Rho-associated protein kinase (ROCK) pathway. The aim of this study was to further confirm AGE-induced angiogenesis in vivo and the involvement of RAGE, ROCK, and moesin phosphorylation in this process. We performed the study in an AGE-treated mouse model with various angiogenesis assays in multiple in vivo and ex vivo models. The results demonstrated that AGEs promoted significant neovascularization in whole mount retina and mouse aortic ring of adult and postnatal mice and in Matrigel plug as well, which were consistently accompanied by increased moesin phosphorylation. The increase of AGE-evoked neovascularization and moesin phosphorylation were both attenuated by RAGE knockout or ROCK inhibitor Y27632 administration in mice. We also revealed the pathological characteristics of AGE-promoted angiogenesis by demonstrating the decrease of pericyte coverage and the disarranged endothelial alignment in microvessels. In conclusion, this study provides in vivo evidences that AGEs induce immature angiogenesis by binding to RAGE, activating the RhoA/ROCK signal pathway and inducing moesin phosphorylation. NEW & NOTEWORTHY Advanced glycation end product (AGE)-induced formation of neovessels and phosphorylation of moesin in retina and aortic ring required AGE receptors. AGEs increased neovessels and the phosphorylation of moesin in retina and aortic ring via RhoA/ROCK pathway. AGE-induced immature angiogenesis in AGE-treated mouse retina and aortic ring. The AGE-RAGE axis and moesin could be candidate targets for overcoming relative diseases.

Azobenzene (Azo) units were successfully introduced into perylene bisimide (PBI) structures in order to realize the photocontrolling of the morphology of the supramolecular assembly of PBI by a photoisomerization process. A total of three Azo-functionalized perylene bisimide derivatives (PBI1, PBI2, and PBI3) with different alkyl chain lengths were designed and synthesized by imidization of 3,4,9,10-perylene tetracarboxylic dianhydride with the corresponding amines. The structures of these compounds were characterized by proton nuclear magnetic resonance (1H NMR) and matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF-MS). The photoisomerization behaviors of Azo units in PBIs were investigated using ultraviolet-visible (UV-VIS) absorption spectroscopy, which were obviously effected by solvents and the alkyl chain length. Furthermore, the photoisomerization of Azo units has the obviously regulatory effect on the morphology of supramolecular assembly of PBIs, especially for the medium-length alkyl chain-linked Azo-functionalized PBI derivative (PBI2). This research realized the photocontrolling of the morphology of the supramolecular assembly of PBI derivatives by photoisomerization of Azo units.

Ligand-receptor molecular recognitionis the basis of biological process. The Saturation Transfer Difference-NMR (STD-NMR) technique has been recently used to gain qualitative and quantitative information about physiological interactions at atomic-resolution. The molecular recognition patterns between Vitamin B12 (VB12) and human serum albumin (HSA) were investigated by STD-NMR supplemented by other spectroscopies and molecular docking. STD-NMR delivered a complete picture that the substituent groups on the tetrapyrrole ring of VB12 interacted with site III of HSA through binding epitope mapping and competitive probe experiments. STD-NMR and fluorescence results proved the moderate binding capability of VB12 and clarified a static, spontaneous, and temperature-sensitive binding mechanism. 3D-fluorencence, FT-IR and circular dichroism spectra showed a compact protein structure by interacting with VB12. Size distribution and surface hydrophobicity showed the surface properties changes of HSA caused by the binding of VB12. Computer simulation confirmed the recognition mode in theory and was compared with experiments. This work is beneficial for understanding the safety and biological action of VB12, and will attract researchers interested in NMR technology.

The structure evolution of surface NiAl2O4 spinel phase in NixAl1O2-δ mesoporous catalysts, synthesized by the citric acid sol-gel method, was systematically investigated. Small-size Ni nanoparticles, obtained by partial reduction from NiAl2O4 spinel in NixAl1O2-δ catalysts with low Ni contents at high temperature, can effectively inhibit the carbon formation from kinetics, while the irreducible NiAl2O4 counterpart can participate in elimination of carbon deposition. The constructed structure of Ni0-NiAl2O4 interfaces, produced by exsolution of Ni from NiAl2O4 spinel, is responsible for its high long-term stability and excellent resistance to coking and sintering for dry reforming of methane (DRM) reaction. The structure sensitivity and kinetic compensation effect of CH4 dissociation on Ni0 active sites are observed. DRM reaction proceeds via a Langmuir-Hinshelwood mechanism accompanied by an additional redox mechanism. It is noteworthy that the active oxygen species generated by filling the oxygen vacancies of NiAl2O4 spinel by CO2 provide another rapid redox route to eliminate carbon species.

A metal-free [2 + 2 + 2] cycloaddition of alkyne-cyanamides or ynamide-nitriles with ynamides is described for the efficient synthesis of amino-substituted α- and δ-carbolines. This novel methodology is environmentally friendly and allows for highly regioselective access to carboline derivatives in good to excellent yields with wide functional group tolerance.

Combing active ester chemistry and click chemistry, a cyclic double-grafted polymer was successfully demonstrated via a &ldquo, grafting onto&rdquo, method. Using active ester chemistry as post-functionalized modification approach, cyclic backbone (c-P2) was synthesized by reacting propargyl amine with cyclic precursor (poly(pentafluorophenyl 4-vinylbenzoate), c-PPF4VB6.5k). Hydroxyl-containing polymer double-chain (l-PS-PhOH) was prepared by reacting azide-functionalized polystyrene (l-PSN3) with 3,5-bis(propynyloxy)phenyl methanol, and further modified by azide group to generate azide-containing polymer double-chain (l-PS-PhN3). The cyclic backbone (c-P2) was then coupled with azide-containing polymer double-chain (l-PS-PhN3) via CuAAC reaction to construct a novel cyclic double-grafted polymer (c-P2-g-Ph-PS). This research realized diversity and complexity of side chains on cyclic-grafted polymers, and this cyclic double-grafted polymer (c-P2-g-Ph-PS) still exhibited narrow molecular weight distribution (Mw/Mn &lt, 1.10).

Grafting has been widely applied to melon (Cucumis melo L.) production to alleviate obstacles of continuous cropping and control soil-borne diseases. However, grafting often leads to a decline of fruit quality. For example, sometimes bitter fruits are produced on grafted plants. However, the underlying physiological mechanism still remains unclear. This study investigated the effects of different rootstocks on the taste of fruits of the Balengcui, an oriental melon cultivar, during summer production. The results showed that all grafted plants with Cucurbita maxima Duch. rootstocks produced bitter fruits, while non-grafted plants and plants grafted onto muskmelon rootstocks produced no bitter fruits. Liquid chromatography-mass spectrometry and metabonomic analysis were performed to investigate the mechanism underlying the occurrence of bitter fruits. Metabolite comparisons of fruits from plants grafted onto Ribenxuesong rootstocks both with non-grafted plants and plants grafted onto muskmelon rootstocks showed that 17 metabolites including phospholipids, cucurbitacins and flavonoids, exhibited changes. The three Cucurbitacins, Cucurbitacin O, Cucurbitacin C, and Cucurbitacin S, increased dramatically. The 10 phospholipids PS(18:1(9Z)/18:2(9Z,12Z)), PS(P-18:0/15:0), PA(18:1(11Z)/18:1(11Z)), PE(16:0/18:0), PS(O-16:0/17:2(9Z,12Z)), PI(16:0/18:2(9Z,12Z)), PA(15:0/22:6(4Z,7Z,10Z,13Z,16Z,19Z)), PS(P-16:0/17:2(9Z,12Z)), PS(22:0/22:1(11Z)), and PA(17:1(9Z)/0:0)) were significantly decreased, while two PA (16:0/18:2 (9Z, 12Z) and 16:0/18:1 (11Z)), two flavonoids (pelargonidin 3-(6''-malonylglucoside)-5-glucoside and malvidin 3-rutinoside) significantly increased in fruits of plants grafted onto Cucurbita maxima Duch. rootstocks. These metabolites were involved in the glycerophospholipid metabolic pathway, the mevalonate pathway, and the phenylpropanoid pathway. In summary, these results showed that the bitter fruits of grafted Balengcui were caused by Cucurbita maxima Duch. rootstocks. Phospholipids, cucurbitacins, and flavonoids were the key contributors for the occurrence of bitter fruits in Balengcui melon after grafting onto Cucurbita maxima Duch. rootstocks.

Background Danshen is a first-line traditional Chinese medicine derived from Salvia miltiorrhiza Bunge consisting mainly of tanshinone IIA, tanshinol, protocatechuic aldehyde, and salvianolic acid B, it is widely used to treat cardiovascular diseases based on the synergistic effect of its multiple active components. Recent studies have indicated that the overall effect of traditional Chinese medicine is closely related to the in vivo coexistence of a variety of active components. Hypothesis The prolongation of the coexistence of the four active components in Danshen in vivo by regulating their pharmacokinetic processes may contribute to better efficiency. Methods/study designs Individual sustained-release pellets of the four main active components in Danshen were respectively prepared according to the optimised formulations developed in our previous studies to modulate their in vivo processes, in which the desired release profiles of each kind of sustained-release pellets for formulation optimisation were calculated based on the point-area deconvolution and circadian rhythm of variant angina. The four kinds of sustained-release pellets were filled into capsules on the basis of the original weight ratio of the four active components in purified Salvia miltiorrhiza extract for further in vitro release and pharmacokinetic and pharmacodynamic investigations. Results The release behaviours of the combined Danshen capsules composed of the four kinds of sustained-release pellets were evaluated in three media with different pH levels (pH 1.2, 6.8, and pure water). The release profiles of each kind of sustained-release pellets in pH 6.8 PBS and pH 1.2 HCl were similar to the release profile of those in pure water (similarity factors f2 > 50). Pharmacokinetic studies revealed that the four kinds of sustained-release pellets in the combined Danshen capsules possessed the same Tmax and similar and extended MRT. Moreover, pharmacodynamic studies indicated that the combined Danshen capsules had much better anti-angina effects than commercial Danshen capsules according to comprehensive evaluations via electrocardiogram, serum index (CK-MB, cTn-I, ET, and NO), myocardial oxidative damage, and myocardial pathologic biopsy. Conclusion Sustained-release preparations can markedly prolong the in vivo coexistence of multiple components in Danshen to enhance their overall effects, which provides a potent strategy for developing the combination therapy of traditional Chinese medicine.

All visible-light-activated Azo photoswitches have recently blossomed. Herein two kinds of photoresponsive Azo hyperbranched polymers, HPTOF and HPTNF, were efficiently synthesized from the respective trinitro-functionalized monomers via combination of the AuNP-catalyzed photocatalytic method and the A3 monomer strategy. The polymerization process showed a very high monomer conversion (>95%) and a perfect selectivity. The molecular weights of the obtained Azo hyperbranched polymers were much higher than those of linear systems as reported previously, which could be efficiently adjusted by controlling the dosages of the mononitro-compound (the end-capping reagent) employed in the polymerization system. The resulting Azo hyperbranched polymers were well characterized by using GPC, NMR, FT-IR and UV-vis spectra. From unusual to common Azo-polymers, the π–π* absorptions in the UV-vis spectra show significant red-shifts; therefore the photoisomerizations of these Azo-polymers (HPTOF and HPTNF) can be induced by visible light. Interestingly, HPTOF and HPTNF demonstrated a double-wavelength (532 nm green light and 313 nm UV light) light-responsive Z → E photoisomerization. The relatively lower photoswitching ability of HPTNF than that of HPTOF was attributed to the partial overlap of π–π* (Z-isomer) and n–π* (E-isomer) transitions resulting from its much longer extending π-conjugation structure.

A novel type of multi-stimuli responsive supramolecular polymer (MRSP) has been successfully constructed based on the self-assembly of heteroditopic macromonomers in a mixed solvent (CDCl3 : CD3CN = 2 : 1, v/v), which contain benzo-21-crown-7 (B21C7) host units and secondary ammonium salt guest moieties at each end of a poly(e-caprolactone) (PCL) chain. Owing to the reversible host–guest complexation between B21C7 and the secondary ammonium salt, the resulting MRSPs exhibit multi-stimuli responsiveness to cations, pH, anions and temperature. More interestingly, nanofibers were facilely obtained via the solution electrospinning of a MRSP, which presented enhanced degradation behaviors in the presence of K+, Cl−, Et3N, or heating, indicating a multiple stimuli-responsive nature.

Combining the ring-closure method with the “grafting from” method, a novel synthetic strategy for preparing cyclic-brush polymers with controlled grafting density was successfully demonstrated. The cyclic polystyrene (c-PS) precursor was synthesized using the general methods of activators generated by electron transfer for atom transfer radical polymerization (AGET-ATRP) and Cu-catalyzed azide–alkyne cycloaddition (CuAAC), and was well characterized using NMR, GPC, MALDI-TOF mass spectroscopy and FT-IR. The benzylic hydrogen atoms of c-PS were substituted with bromine based on Wohl–Ziegler bromination to generate a tertiary bromide ATRP macroinitiator (c-PSBr), and the bromine content can be adjusted to 18.4%, 25.3%, 31.9% and 50.3% by using different reaction conditions. This ATRP macroinitiator can also be converted into a macro-RAFT agent with azole (c-PSN) or ethyoxyl (c-PSO) as the Z groups based on the styrenic polymers as the R group. Using the as-prepared ATRP macroinitiator or macro-RAFT agents, a series of cyclic-brush polymers including c-PS-g-PS, c-PS-g-PNIPAM, c-PS-g-PMMA, c-PS-g-PMA and c-PS-g-PVAc were successfully prepared. The grafting density can be facilely tuned by using variable Br content of c-PSBr or Z group content of the macro-RAFT agents. The work illustrated a first example of versatile synthesis of cyclic-brush polymers with predictable molecular weight, grafting density and different grafting polymer chains.

Cardiomyocyte apoptosis is a major event in the pathogenesis of diabetic cardiomyopathy. Currently, no single effective treatment for diabetic cardiomyopathy exists. The present study investigated whether advanced oxidative protein products (AOPPs) have a detrimental role in the survival of cardiomyocytes and if glucagon-like peptide-1 (GLP-1) exerts a cardioprotective effect under these circumstances. The present study also aimed to determine the underlying mechanisms. H9c2 cells were exposed to increasing concentrations of AOPPs in the presence or absence of GLP-1, and the viability and apoptotic rate were detected using a cell counting kit-8 assay and flow cytometry, respectively. In addition, a phosphatidylino-sitol-4,5-bisphosphate 3-kinase (PI3K) inhibitor, LY294002, was employed to illustrate the mechanism of the antiapoptotic effect of GLP-1. The expression levels of the apoptotic-associated proteins, Akt, B-cell lymphoma (Bcl)-2, Bcl-2-associated death promoter (Bad), Bcl-2-associated X protein (Bax) and caspase-3 were measured by western blotting. It was revealed that GLP-1 significantly attenuated AOPP-induced cell toxicity and apoptosis. AOPPs inactivated the phosphorylation of Akt, reduced the phosphorylation of Bad, decreased the expression of Bcl-2, increased the expression of Bax and the activation of caspase-3 in H9c2 cells. GLP-1 reversed the above changes induced by AOPPs and the protective effects of GLP-1 were abolished by the PI3K inhibitor, LY294002. In conclusion, the present data suggested that GLP-1 protected cardiomyocytes against AOPP-induced apoptosis, predominantly via the PI3K/Akt/Bad pathway. These results provided a conceivable mechanism for the development of diabetic cardiomyopathy and rendered a novel application of GLP-1 exerting favorable cardiac effects for the treatment of diabetic cardiomyopathy.

Nomilin is a potential anticancer agent. In this study, a rapid, sensitive, and simple ultra-performance liquid chromatography with tandem mass spectrometry methodology was established and validated to quantify nomilin in rat plasma. Plasma samples were prepared through liquid-liquid extraction using ethyl acetate. Chromatographic separation was performed using an Acquity HSS T3 column. Acetonitrile and water containing 0.1 % (v/v) formic acid were used as mobile phases at a flow rate of 0.3 mL/min. Nomilin and quercetin (internal standard) were detected and quantified via a triple quadrupole tandem mass spectrometer in the positive ion mode with multiple reaction monitoring. Tandem mass spectrometry detection was performed by monitoring the fragmentations of m/z 515.3 → m/z 161.0 and m/z 303.2 → m/z 153.1 of nomilin and quercetin, respectively. Good linearity (R2 > 0.996) was observed in the concentration range of 1 ng/mL to 500 ng/mL with a lower limit of quantification of 1 ng/mL for nomilin. The average extraction recoveries of nomilin and quercetin were > 82.3 % and 82.0 %, respectively. Intra- and interday precisions were less than 15 % and accuracy ranged from 85.0 % to 90.1 %. Indeed, the proposed method was successfully applied to analyze the pharmacokinetics of nomilin after 3 and 50 mg/kg nomilin were administered to rats via intravenous and oral routes, respectively.

The entrance flow of long glass fiber reinforced polypropylene has been studied. It is demonstrated that longer glass fibers are easier to break and accumulate at the entrance. As the length of the die and shear rate increase, the fiber breakage increases for long glass fiber reinforced polypropylene. Comparison of fiber breakages of long and short glass fiber reinforced polypropylene indicates that short glass fiber mainly breaks before and at the entrance and remains almost unchanged in the die, while longer glass fibers still break after the entrance within the die. It is demonstrated that fiber accumulation increased when increasing the length of the die and shear rate. The pressure is found to oscillate at the entrance and this pressure accumulation and release should be related to the fiber interactions and fiber breakage at the entrance. It is also found that the presence of long glass fibers would lead to significantly higher viscosity which would decrease when increasing the shear rate.

Ternary Ag nanoparticles (NPs)@polyoxometalate (POM)/reduced graphene oxide (rGO) nanohybrids were prepared by a facile photoreduction method, using POM as the photocatalyst, reducing and bridging molecules. The structure of the nanohybrids was characterized by transmission electron microscopy, X-ray photoelectron spectroscopy, X-ray diffraction, Raman spectroscopy, etc. Most importantly, both the rotating disk electrode and rotating ring-disk electrode tests indicated that the Ag NPs@POM/rGO nanohybrids exhibited excellent electrocatalytic activity towards oxygen reduction reaction via a direct four-electron transfer pathway due to the synergistic effect of Ag NPs and rGO.

The Co-7(AlePy)(2) polyoxometalate, which encloses a {(PW9)(2)Co-7(II)} core covalently bound to two free aminopyridine groups through bisphosphonate ligands (AlePy), has been isolated. It can be used as a precursor, allowing the synthesis of heterometallic hybrid compounds, as illustrated by the characterization of cobalt/zinc (Co-7(AlePyZn)(2)), cobalt/palladium (Co-7(AlePyPd)(2)), and cobalt/platinum (Co-7(AlePyPt)(2)) species. A composite based on the water-insoluble precious metal-free Co-7(AlePyZn)(2) compound and the low-cost carbon material Vulcan XC-72 has been selected as a cathode material (Co7Zn/C) for oxygen reduction reaction studies. The electrocatalytic performances of the Co7Zn/C hybrids were assessed at neutral and basic pH, showing that Co7Zn/C exhibits high selectivity for the four-electron reduction of O-2. Moreover, its durability is superior to that of a commercial Pt/C catalyst with 20% loading. Also, comparative studies performed in the presence of methanol have indicated that Co7Zn/C has a much better tolerance to the crossover effect than Pt/C. Altogether, these results indicate for the first time that, even in neutral media, polyoxometalate/carbon composites can represent low-cost oxygen reduction catalysts that can function stably, for a long time, and with high performance.

A series of in vitro evaluation in our previous studies had proved that arachidonic acid (AA) modification could suppress the remodeling behaviors of lovastatin-loaded discoidal reconstituted high density lipoprotein (LT-d-rHDL) by restraining the reactivity with lecithin cholesterol acyltransferase (LCAT) for reducing undesired drug leakage. This study focuses on the investigation of AA-modified LT-d-rHDL (AA-LT-d-rHDL) in atherosclerotic New Zealand White (NZW) rabbit models to explore whether AA modification could enhance drug targeting delivery and improve antiatherogenic efficacies in vivo.After pharmacokinetics of AA-LT-d-rHDL modified with different AA amount were investigated in atherosclerotic NZW rabbits, atherosclerotic lesions targeting property was assessed by ex vivo imaging of aortic tree and drug distribution. Furthermore, their antiatherogenic efficacies were elaborately evaluated and compared by typical biochemical indices.With AA modification amount augmenting, circulation time of AA-LT-d-rHDL was prolonged, and drug accumulation in the target locus was increased, eventually the significant appreciation in antiatherogenic efficacies were further supported by lower level of bad cholesterol, decreased atherosclerotic lesions areas and mean intima-media thickness (MIT), markedly attenuated matrix metalloproteinase-9 (MMP-9) protein expression and macrophage infiltration.This proof-of-concept study demonstrated that AA-LT-d-rHDL could enhance drug accumulation in atherosclerotic lesion and impede atherosclerosis progression more effectively.

Gelsemine from Gelsemium elegans Benth is a potential anesthetic and analgesic agent with no physical dependence and opiate addiction. This study was aimed at developing an ultrafast liquid chromatography coupled to tandem mass spectrometry method to quantify gelsemine in rat plasma and tissues. Plasma and tissues were processed with acetonitrile precipitation, and dendrobine was chosen as the internal standard. Sample separation was performed on an ACQUITY HSS T3 column. The mobile phase consisted of acetonitrile and 0.1% formic acid aqueous solution. Multiple reactions monitoring mode was utilized to detect the compounds of interest. The mass spectrometer was operated in the positive ion mode for detection. The MS/MS ion transitions monitored were m/z 323.2→70.5 for gelsemine and 264.2→108.05 for dendrobine, respectively. The calibration curves were linear over the range of 1-500 ng/mL in all biological matrices. The lower limit of quantification for rats plasma and tissues was 1.0 ng/mL. The values for inter- and intraday precision and accuracy were well within the ranges acceptable (< 15%). It was successfully applied to the pharmacokinetic and tissue distribution studies of gelsemine after intravenous doses of 5, 2, and 0.5 mg/kg in rats. These data of gelsemine would be useful for clinical application and further development.

An anthranol derivative (DTDDP) and an anthraquinone derivative diastereomer (DDDP) without typical donor–acceptor (D–A) structural features were synthesized from 1,4-diaminoanthraquinone via a one-step reaction. The absorption and fluorescence emission properties of DTDDP and DDDP were investigated in common organic solvents with different polarity. In spite of a lack of apparent D–A structure, DTDDP exhibited apparent solvatochromic fluorescence emission with shift >80 nm in aprotic media. The linear correlation of the Stokes shift of DTDDP in a Lippert–Mataga plot was observed, and the change in the dipole moment of DTDDP upon excitation, 10.7 D, was determined. Time-dependent density functional theory (TDDFT) calculation confirmed the marked hole–electron separation of the excited DTDDP molecule as compared to that of the excited DDDP molecule. The experimental results and the theoretical calculation revealed the excited-state intramolecular charge-transfer nature of the emitting state of DTDDP molecu...

Well-defined α-fluorinated alkyl ester, ω-carboxyl telechelic polystyrenes (PS) were synthesized via combining aminolysis of RAFT-polystyrene and thiol–ene “click” reaction simultaneously. The perfluoroalkyl end groups were –CF3, –(CF2)2–CF3 and –(CF2)7–CF3, respectively. Highly ordered porous films of such telechelic PS with an average pore size about 1.00 μm were fabricated via a static breath-figure process. With the content of fluorine on the surface of porous films increasing from 1.04 wt%, to 1.64 wt% and 2.97 wt%, respectively, the water contact angle (WCA) of such porous films increased from 112° to 116° and 121° ± 0.4°, respectively, indicating their hydrophobicity. Interestingly, microspheres with average diameters of ca. 0.30–0.65 μm can be fabricated via a static BF process using methanol instead of water as the vapor atmosphere in the glass vessel.

Jujuboside B (JuB) is a main bioactive saponin constituent of Ziziphi Spinosae Semen. The compound is used clinically as an anti-insomnia and anti-anxiety medicine. In this study, a sensitive, simple, and rapid ultra performance liquid chromatography with tandem mass spectrometry (UPLC-MS/MS) was developed and validated to quantify JuB in rat plasma. A simple protein-precipitation method was used to extract JuB from rat plasma samples. Jujuboside A was used as an internal standard (IS). Chromatographic separation was performed using an Acquity HSS T3 column. The mobile phase consisted of acetonitrile and 0.1% formic acid in water with a flow rate of 0.3 mL min−1. Identification and quantification were performed through electrospray ionization in a negative mode with multiple reaction monitoring of JuB and IS transitions of m/z 1043.3 → 911.5 and m/z 1205.6 → 1073.4, respectively. The calibration curve was linear in the range of 0.1 ng mL−1 to 1000 ng mL−1 (R2 = 0.990) with a limit of detection of 0.03 ng mL−1. The extraction recoveries of JuB were 90.3% to 95.7% and the precisions of intra-and inter-day were less than 11.5%. The matrix effect of JuB at three different concentrations ranged from 93.5% to 95.9% with a standard deviation of

New polymethylene-based AB2 star polymers with well-defined architecture and various components were synthesized using a combination of polyhomologation of ylides and atomic transfer radical polymerization (ATRP). The chain structures of polymethylene-b-(polystyrene)2 (PM-b-(PS)2) and polymethylene-b-(poly(methyl methacrylate))2 (PM-b-(PMMA)2) were characterized through 1H NMR, GPC and FT-IR. The porous films of such star copolymers were fabricated via a static breath-figure (BF) process. The influence of polymer molecular weight, solution concentration and environmental temperature on the morphology of such block copolymer films was investigated. The porous surface of such a film presents hydrophobic behaviour with a static water-droplet contact angle of ca. 108°. The electrospinning of PM-b-(PS)2 was performed using CHCl3 as a solvent and the wrinkle-like polymer particles with nanopores on their surface were obtained.

Cyclic poly(4-bromostyrene) (c-PBrS), synthesized via a combination of atom transfer radical polymerization (ATRP) and copper(I)-catalyzed azide-alkyne cycloaddition (CuAAC), was employed as a universal cyclic precursor to prepare cyclic-brush polymers by the Suzuki coupling reaction. Cyclic functional poly[(4-methoxyphenyl)styrene] and cyclic-brush polystyrene have been achieved by the Suzuki coupling reaction as a post-modification, endowing excellent modification efficiency (∼100%), i.e., all the repeating units have been completely transformed into target ones. The obtained polymer structures were carefully characterized by NMR, GPC and MALDI-TOF mass spectra. This study undoubtedly offers a highly efficient and promising post-modification protocol to prepare cyclic-brush polymers or other more complex ones, the preparation of which was previously highly challenging.

A thiol–ene “click” reaction proceeds with facile reaction conditions for complete conversion, and displays a higher tolerance to various backbones and functional groups compared with traditional coupling and functionalization strategies. Herein, well-defined α,ω-telechelic polystyrenes with trithiocarbonate and carboxyl terminal groups (PS-CTA) were firstly synthesized via reversible addition-fragmentation chain transfer (RAFT) radical polymerization. Then, the terminal thiol group was converted from the thiocarbonylthio end group of PS-CTA and subsequently reacted with n-butyl acrylate and vinyl ferrocene, respectively, through thiol–ene “click” chemistry, to achieve α,ω-telechelic polystyrenes with difunctionality. Alternatively, a facile one-pot simultaneous aminolysis and thiol–ene “click” reaction using PS-CTA and various ene-bearing compounds as reactants was found to have high efficiency in synthesizing diverse α,ω-telechelic polystyrenes with di- and tri-functionality. Various functional groups such as hydroxyl, acrylate, fluorinated acrylate, ferrocene and allyl, etc. can be successfully incorporated as terminal groups of α,ω-telechelic polystyrenes.