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CPL-active microspheres and microcrystals are fabricated via the reaction and co-assembly of pyridine derivatives with a chiral phosphoric acid.

The first proton transfer type HOF based on two-component TTF derivatives.

A synthetic approach to dibenzo[f,h]quinolines and their derivatives via stepwise ruthenium-catalyzed C–H arylation and potassium-mediated reductive cyclodehydrogenation from 2-phenylpyridine and aryl bromides, is presented. One dibenzo[f,h]quinoline derivative is used as a bidentate ligand to prepare a cyclometalated ruthenium complex. Two dibenzo[f,h]quinoline compounds and the ruthenium complex were characterized by single-crystal X-ray structural analysis.

Herein, a nanopipette-based thermocouple probe that possesses high temperature resolution, rapid response, good reversibility and stability was constructed and successfully applied for single-cell temperature sensing. Different intracellular temperatures were observed in diverse types of cells, which reveals differences in their metabolism levels. Temperature responses of cancer and normal cells against various exogenous drugs were also demonstrated. The spatially resolved temperature sensing of three-dimensional cell culture models unveils the existence of their inner temperature gradients. This work would facilitate drug screening and disease diagnosis.

Pomalidomide is an immunomodulatory agent (IMiD) that has been approved by the US Food and Drug Administration (FDA) for clinical treatment of patients with multiple myeloma. In this work, we developed a sensitive and validated LC-MS/MS method for high-throughput determination of pomalidomide over the range of 1.006–100.6 ng/mL (R2 = 0.9991) in human plasma and pharmacokinetic studies. A liquid-liquid extraction method using ethyl acetate was applied to extract pomalidomide and afatinib (as an internal standard, IS) from human plasma. Chromatographic separation was performed on a Hedera ODS column (150 mm × 2.1 mm, 5 μm) with security guard C18 column (4 mm × 2.0 mm) at 40 °C. Methanol and 10 mmol/L aqueous solution of ammonium acetate containing 0.1% formic acid were used as a gradient elution mobile phase, and the flow rate was 0.4 mL/min. A triple quadruple tandem mass spectrometer using multiplex reaction monitoring mode (MRM) with electrospray ionization (ESI) positive ionization was employed. The precursor to product ion transitions for the quantitative analysis of pomalidomide and the IS were m/z 274.2→163.1 and m/z 486.1→371.1, respectively. This established method has been validated according to regulatory guideline, and the results were all within the acceptance criteria. The validated LC-MS/MS method was successfully applied to analyze samples obtained from clinical pharmacokinetics study after oral administration of pomalidomide (4 mg) capsules in human.

Harvesting the low-grade (

This review centers on a closed bipolar electrode (BPE) array using an electro-fluorochromism (EFC) or electro-chemiluminescence (ECL) reaction as the reporting reaction. Electrochemical signals at one pole of the closed BPE array can be transduced into the EFC or ECL signals at the opposite pole. Therefore, the current signal of a redox reaction can be easily detected and imaged by monitoring the luminescence signal. Recent developments in closed BPE array-based EFC and ECL sensing and imaging are summarized and discussed in detail. Finally, we consider the challenges and opportunities for improving the spatial resolution of closed BPE array-based electrochemical imaging, and emphasize the important application of this technique to the imaging of cellular activities at the single-cell level.

A crack-free micrometer-sized compact structure of 1,3,5-tris(4-aminophenyl)benzene-terephthaldehyde-covalent organic frameworks (TAPB-PDA-COFs) was constructed in situ at the tip of a theta micropipette (TMP). The COF-covered theta micropipette (CTP) then created a stable liquid-gas interface inside COF nanochannels, which was utilized to electrochemically analyze the content and distribution of ammonia gas in the microenvironments. The TMP-based electrochemical ammonia sensor (TEAS) shows a high sensing response, with current increasing linearly from 0 to 50,000 ppm ammonia, owing to the absorption of ammonia gas in the solvent meniscus that connects both barrels of the TEAS. The TEAS also exhibits a short response and recovery time of 5 ± 2 s and 6 ± 2 s, respectively. This response of the ammonia sensor is remarkably stable and repeatable, with a relative standard deviation of 6% for 500 ppm ammonia gas dispensing with humidity control. Due to its fast, reproducible, and stable response to ammonia gas, the TEAS was also utilized as a scanning electrochemical microscopy (SECM) probe for imaging the distribution of ammonia gas in a microspace. This study unlocks new possibilities for using a TMP in designing microscale probes for gas sensing and imaging.

Biological ion pumps with two separate gates can actively transport ions against the concentration gradient. Developing an artificial nanofluidic device with multiple responsive sites is of great importance to improve its controllability over ion transport to further explore its logic function and mimic the biological process. Here, we propose an electrochemical polymerization method to fabricate electrochemically switchable double-gate nanofluidic devices. The ion transport of the double-gate nanofluidic device can be in situ and reversibly switched among four different states. The logic function of this nanofluidic device is systematically investigated by assuming the gate state as the input and the transmembrane ionic conductance as the output. A biomimetic electrochemical ion pump is then established by alternately applying two different specific logic combinations, realizing an active ion transport under a concentration gradient. This work would inspire further studies to construct complex logical networks and explore bioinspired ion pump systems.

Ion transport in nanochannels of a size comparable to that of hydrated ions exhibits unique properties due to the synergistic effect of various forces. Here, we design a nanochannel/ion channel composite (NIC) membrane that shows a high ion current rectification (ICR) ratio in different electrolytes. Experimental and theoretical results demonstrate that the synergistic effect of electrostatic interaction and ionic dehydration plays an important role in regulating the ICR behavior of the NIC membrane. We find that electrostatic attraction between ions and the channel surface in the ultraconfined space increases the probability of ionic dehydarion, resulting in different dehydration energy costs for different ions. This further alters the driving force for ion transport and thus regulates ICR of the NIC membrane. This work provides fundamental knowledge of ion transport in ion channels, which aids in the understanding of the function of biological systems and the design of high-performance nanochannel devices.

A new class of high-quality ionic organic microcrystals with bright deep-blue luminescence (with up to 60% quantum yield) have been prepared in situ by the protonation of 2,2′-di(pyrid-2-yl)bipheny...

Objective: To explore the characteristics of ZHANG Zhongjing's medication for constipation by analyzing the prescriptions of treatise on Shanghan Lun and Jingui Yaolue. Methods: the formulations that met the inclusion criteria were selected to establish a database, and the regularity of ZHANG Zhongjing's medication for constipation was analyzed by the methods of frequency, association rules and clustering. Results: In this study, 11 prescriptions and 24 medicines were included. High-frequency use of drugs rhubarb, licorice, CortexMagnoliae Officinalis ,fructus aurantii immaturus , mirabilis, ginger, jujube,white atractylodes rhizome , cassia twig,Chinese herbaceous peony . A total of 17 association rules (11 rules for 2 drugs and 6 rules for 3 drugs) were obtained by mining, including"Rhubarb + Mirabilite", "fructus aurantii immaturus + Cortex Magnoliae Officinalis", "Rhubarb + Cortex Magnoliae Officinalis", "Rhubarb +Cortex Magnoliae Officinalis +fructus aurantii immaturus ", and so on, and 7 groups of drug pair association group and 2 groups of multi-flavor drug association group were obtained. Network link analysis shows that there are 7 groups of strong link compatibility. Medium link compatibility 46 groups. Cluster analysis obtained 14 groups, including 8 single-taste drug groups, 3 drug-pair polymerization groups and 3 multi-taste drug polymerization groups. Conclusions: ZHANG Zhongjing is not only good at using purgative medicine in treating constipation treating constipation, but also pays attention to invigorating qi and activating blood circulation, resolving the surface and regulating dampness, soothing the liver and regulating qi.

High ion selectivity and permeability, as two contradictory aspects for the membrane design, highly hamper the development of osmotic energy harvesting technologies. Metal-organic frameworks (MOFs) with ultra-small and high-density pores and functional surface groups show great promise in tackling these problems. Here, we propose a facile and mild cathodic deposition method to directly prepare crack-free porphyrin MOF membranes on a porous anodic aluminum oxide for osmotic energy harvesting. The abundant carboxyl groups of the functionalized porphyrin ligands together with the nanoporous structure endows the MOF membrane with high cation selectivity and ion permeability, thus a large output power density of 6.26 W m

Conventional square-planar platinum complexes typically form one-dimensional assemblies as a result of unidirectional metallophilic and/or π⋅⋅⋅π intermolecular interactions. Organoplatinum(II) complexes with a cruciform shape are presented herein to construct two-dimensional (2D) microcrystals with full-color and white phosphorescence. These 2D crystals show unique monocomponent π⋅⋅⋅π stacking, from either the cyclometalating or noncyclometalating ligand, and the bicomponent alternate π⋅⋅⋅π stacking from both ligands along different facet directions. Anisotropic tri-directional waveguiding is further implemented on a single hexagonal microcrystal. These results demonstrate the great capability of the organoplatinum(II) cruciform as a general platform to fabricate 2D phosphorescent micro-/nanocrystals for advanced photonic applications.

The addition of heavy protein to aquafeed causes low digestibility, high cost and significant nitrogen pollution in the water. The addition of protease is an effective way of improving protein absorption, but few proteases have been developed specifically for aquafeeds. The hydrolysis efficiency of protease additives for plant protein in the neutral gut environment and their synergy with endogenous proteases has not been sufficiently investigated. In this study, the performance of the recombinant neutral protease rNpI as an aquafeed additive to reduce the raw protein materials in the diet of Carassius carassius during 56 days of growth was evaluated. rNpI effectively hydrolysed soya bean protein isolates (SPI) with a high degree of hydrolysation and a high small‐peptide yield. The rNpI‐treated SPI exhibited a notable antioxidant activity, which benefited fish health. In vitro digestibility indicated that rNpI complemented trypsin in SPI digestion better than papain or Alcalase. The growth trial showed that the addition of rNpI could warrant a reduction in the crude protein and gross energy of feed while producing a lower feed‐conversion rate (FCR) and better growth performance. Crucian that were fed an RM‐wheat‐E diet (5.5% rapeseed meal and 5% wheat reduction) showed the best performance, with the lowest FCR and highest weight gain. These results indicate that rNpI could be an effective additive for the aquafeed industry and could provide economic benefits by reducing aquafeed protein requirements and nitrogen emissions. This study provides novel information and strategies for additive protease use and development in aquafeed.

The bottom-up functionalization of solid surfaces shows increasing importance for a wide range of interdisciplinary applications. Multidentate anchors with more than two contact points can bind to solid surfaces with strong chemisorption, well-defined upright configuration, and tailored functionality. The surface functionalization using multidentate anchors with three (tripodal), four (quadripodal), or more binding points is summarized herein, with a focus on those beyond classical tripodal anchors. In particular, the molecular design on how to achieve multisite interaction between anchor and substrate and the introduction of functional groups to thin films are discussed.

Ion transport in bionanopores is closely related to biological processes and can be regulated by various external stimulations. Multivalent ion as one of the stimulators shows a great ability in tu...

Protein drugs showing strong pharmaceutical activity, high specificity, and low toxicity and side effects have drawn extensive attention in the field of life sciences and medicine. Precise evaluation of the function of these drugs requires accurate and sensitive detection methods. Here, we report a novel chromatography-tandem mass spectrometry (LC-MS/MS) method for sensitive and selective detection of protein drugs. Magnetic nanoparticles (Apt29@MNPs) were functionalized by thrombin aptamers, and quantum dots (Apt15@ss@QDs) were dual-functionalized with quantitative thrombin aptamers and small molecules with high ionization efficiency as the mass barcode. After Apt29@MNPs specifically purify and enrich thrombin from biological samples, they can form a nano "sandwich structure" when Apt15@ss@QDs are added, resulting in the release of the mass barcode for LC-MS/MS analysis via the cutting of the disulfide bond. Since there is a higher quantitative molecular ratio of mass barcode to thrombin in the nano-"sandwich structure", quantitative detection of thrombin with high sensitivity and selectivity can be achieved via the LC-MS/MS detection of the mass barcode with high ionization efficiency rather than thrombin, which effectively avoids the disadvantages of direct protein detection by mass spectrometry. The established method for thrombin detection shows a good linear relationship in a concentration range of 0.00115-1.15 nM with a limit of detection (LOD) of 0.0007 nM. The present work provides a new approach for the effective and sensitive quantitative analysis of protein drugs and would be of great significance in promoting the development of protein drugs and clinical applications.

Nanoelectrode arrays have been widely used in electroanalytical applications. The challenge is to develop low-cost and simple approaches to the fabrication of superuniform and ultrasmall nanoelectrode arrays for improving analytical performance and imaging resolution. Here, superuniform and high-density gold nanoelectrode arrays with tunable electrode diameters and interelectrode distances have been fabricated by electrodeposition, followed by a simple mechanical polishing process. The fabricated free-standing arrays have a high density (108 cm-2) of nanoelectrodes (60, 140, and 200 nm in diameter), and can be used as closed bipolar electrode arrays to image electrochemical heterogeneity with micrometer spatial resolution. With the help of a confocal microscope, individual nanoelectrodes can be visualized and resolved from the reflected light. Thus, the nanoelectrode arrays are promising in electrochemical imaging with high spatial resolution.

Conventional ion current-based nanopore techniques that identify single molecules are hampered by limitations of providing only the ionic current information. Here, we introduce a silver nanotriangle-based nanopore (diameter < 50 nm) system for detecting molecule translocation using surface-enhanced Raman scattering. Rhodamine 6G is used as a model molecule to study the effect of an electric field (-1 V) on the mass transport. The four DNA bases also show significantly different SERS signals when they are transported into the plasmonic nanopore. The observations suggest that in the electric field, analyte molecules are driven into the nanopipette through the hot spot of the silver nanopore. The plasmonic nanopore shows great potential as a highly sensitive SERS platform for detecting molecule transport and paves the way for single molecule probing.

To investigate the mechanism of Coptidis Rhizoma-Pinelliae Rhizoma in the treatment of gastric cancer based on syste-matic pharmacology and data mining. The chemical constituents of Coptidis Rhizoma and Pinelliae Rhizoma were obtained from Traditio-nal Chinese Medicine Systems Pharmacology Database(TCMSP) and Shanghai Institute of Organic Chemistry database of Chinese Academy of Sciences by data mining. Then the active ingredients were screened by ADME, and the targets of the active ingredients were predicted by chemometrics. Molecular docking and free energy analysis were used to verify and screen the targets, so as to obtain the therapeutic targets of Coptidis Rhizoma and Pinelliae Rhizoma for gastric cancer. The biological functions, diseases and related signal pathways corresponding to the targets were further analyzed, and then the multi-component, multi-target and multi-channel mechanism of Coptidis Rhizoma and Pinelliae Rhizoma for gastric cancer were elaborated. Finally, MTT, Scratch, Transwell and Western blot experiments were carried out to verify the inhibitory effect of Coptidis Rhizoma and Pinelliae Rhizoma on human gastric cancer cell line MKN-45. A total of 46 active ingredients of Coptidis Rhizoma and Pinelliae Rhizoma were screened, as well as 77 corresponding targets, 38 targets related to gastric cancer and its complications, top 8 related signaling pathways, and top 20 target molecular functions by GO analysis. Cell experiments also proved that Coptidis Rhizoma and Pinelliae Rhizoma could effectively inhibit the proliferation, invasion and migration ability of gastric cancer cells and inhibit TGF-β1-induced Wnt/β-catenin signaling pathway activation. Coptidis Rhizoma and Pinelliae Rhizoma drug pair has many active ingredients, which can regulate nervous and mental system, cell cycle, cell differentiation and metastasis, and enhance anti-inflammatory and immune functions, playing a synergistic anti-cancer role in gastric cancer and its complications and providing new ideas for the follow-up clinical treatment of gastric cancer.

Membrane-based ion separation is environmentally friendly, energy-efficient, and easy to integrate, being widely used in water desalination and purification systems. With the existing separation technologies, it is yet difficult to achieve real time, in situ, and reversible control of the separation process. Here, we design and fabricate a Prussian blue (PB) coordination polymer based membrane with uniform and electrochemically size-tunable subnanopores. The ion separation can be significantly and reversibly modulated through the electrochemical conversion between PB and Prussian white (PW). The permeation rates of small hydrated metal ions (Cs+ and K+) obviously increase upon switching from PB to PW, while the permeation rates of large hydrated metal ions (Li+, Na+, Mg2+, and La3+) remain constant. The membrane selectivity of small hydrated ions to large hydrated ions can be increased by more than 2 times during the electrochemical switch, which could be assigned to the slightly larger crystal size (e.g., pore window size) of PW than PB. The present approach provides a new strategy for constructing tunable seawater desalination and ion extraction systems.

The unique phenomena of ion selectivity and ion current rectification (ICR) in nanofluidics have been widely used to construct bioinspired channels and organs, sensors, and power generators. However, the excellent performance of a single nanochannel does not show a linear increase when it is scaled up into multiple nanochannels in tandem and parallel structure, and in some cases, it even shows a reverse trend. Understanding of this scaling-up inconsistency in nanofluidics is essential to the design of functional devices. Here, we provide a method for investigating the ion transport properties in multiple nanochannels in tandem and parallel connections. We find that interfacial resistance caused by ion concentration polarization (ICP) in tandem and parallel nanochannels has a significant impact on ICR, showing a nonlinear scaling-up feature with the tandem number and a decreased trend with the parallel number, which is not expected in electronic devices. We further verify that it is feasible to regulate ion transport in tandem and parallel nanochannels by adding gap distances between nanochannels in tandem and parallel structures to decouple the ICP region between nanochannels. This study provides fundamental insights into the ion transport properties in nanofluidic circuits, which hold promise for the design of high-performance nanofluidic devices in the fields of separation, energy, and sensors.

A novel and efficient photochemical method has been proposed for the encapsulation of Prussian blue nanoparticles (PBNPs) inside the channels of carbon nanotubes (PB-in-CNTs) in an acidic ferrocyanide solution under UV/vis illumination, and the confinement effect of CNTs on the electrochemical properties of PBNPs is systematically explored. PB-in-CNTs show a faster electron-transfer process, an enhanced electrocatalytic activity toward the reduction of H2O2, and an increased anti-base ability compared to PBNPs loaded outside of CNTs (PB-out-CNTs). In addition, PB-in-CNTs show an increased electrochemical reversibility and an unexpected diameter-independent catalytic activity with the decrease of CNT diameters. The improved electrochemical properties of PB-in-CNTs are attributed to the modified electronic properties and dimensions of PBNPs induced by the confinement effect of CNTs. This work provides further insights into the confinement effect on the properties of nanomaterials and will inspire extensive ...

For study of the photocatalytic reaction kinetics in a confined microsystem, a photocatalysis microreactor integrated on a microfluidic device has been fabricated using an on-line UV/vis detector. The performance of the photocatalysis microreactor is evaluated by the photocatalytic degradation of Rhodamine B chosen as model target by using commercial titanium dioxide (Degussa P25, TiO2) nanoparticles as a photocatalyst. Results show that the photocatalytic reaction occurs via the Langmuir-Hinshelwood mechanism and the photocatalysis kinetics in the confined microsystem (r = 0.359 min−1) is about 10 times larger than that in macrosystem (r = 0.033 min−1). In addition, the photocatalysis activity of the immobilized TiO2 nanoparticles in the microreactor exhibits good stability under flowing conditions. The present microchip device offers an interesting platform for screening of photocatalysts and exploration of photocatalysis mechanisms and kinetics.

The transcription factor forkhead box N1 (Foxn1) plays an important role in the development and function of thymic epithelial cells (TECs) in vertebrates. However, the transcriptional regulation of Foxn1 is still unknown. A series of dual luciferase report vectors were constructed and their relative activities were also detected. The 5'-untranslated regions contains two cis-acting elements, Sp1 and GATA-1, as well as trans-acting elements between positions -332 to -438. Nevertheless, the relative activities of Foxn1 promoter were significantly increased in PK15 cells only when the Sp1 was overexpressed, suggesting that the Sp1 was the most important sequence for Foxn1 transcription activation in the pig. Regrettably, the exact trans-acting elements were not found.

Detection of cancer biomarker is of great significance in cancer diagnostics. In this work, we propose an ultrasensitive and in situ method for plasmon enhanced Raman scattering (PERS) detection of nucleolin (NCL) using a 3D hybrid plasmonic metamaterial (PM). In this aptasensor, thiolated complementary DNA (cDNA) immobilized on PM can hybridize with Rox-labeled NCL-binding aptamer (AS1411-Rox) to form a rigid double-stranded DNA (dsDNA). When NCL passes through the PM nanochannels under a transmembrane voltage bias, it interacts with AS1411-Rox to form G-quadruplexes (G4-AS1411-Rox), resulting in the release of AS1411-Rox from the nanochannels surface and the decrease in PERS signal of the reporter Rox. This change in PERS signals can be recorded in situ without the interference of external environment. With the help of the enrichment function of nanochannel, the present method is able to achieve fast NCL detection within 10 min with a detection limit as low as 71 pM. Furthermore, our method shows excellent specificity, reversibility, uniformity (relative standard deviation of ~6.86%) and reproducibility (~6.65%), providing a new platform for reliable cancer auxiliary diagnosis and drug screening.

Combination therapy, especially photodynamic/photothermal therapy (PDT/PTT), has shown promising applications in cancer therapy. However, sequential irradiation by two different laser sources and even the utilization of single high-power laser to induce either combined PDT/PTT or individual PTT will be subjected to prolonged treatment time, complicated treatment process, and potential skin burns. Thus, low power single laser activatable combined PDT/PTT is still a formidable challenge. Herein, we propose an effective strategy to achieve synergistic cancer phototherapy under low power single laser irradiation for short duration. By taking advantage of dual plasmonic PTT nanoagents (AuNRs/MoS2), a significant increase in temperature up to 60 °C with an overall photothermal conversion efficiency (PCE) of 68.8% was achieved within 5 min under very low power (0.2 W/cm2) NIR laser irradiation. The enhanced PCE and PTT performance is attributed to the synergistic plasmonic PTT effect (PPTT) of dual plasmonic nan...