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  • 1.

    【2hr】Back-Side Polymer-Coated Solid-State Nanopore Sensors

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    机译 背面聚合物涂层固态纳米孔传感器
    摘要：We systematically investigated the influence of polymer coating on temporal resolution of solid-state nanopores. We fabricated a Si3N4 nanopore integrated with a polyimide sheet partially covering the substrate surface. Upon detecting the nanoparticles dispersed in an electrolyte buffer by ionic current measurements, we observed a larger resistive pulse height along with a faster current decay at the tails under larger coverage of the polymeric layer, thereby suggesting a prominent role of the water-touching Si3N4 thin film as a significant capacitor serving to retard the ionic current response to the ion blockade by fast translocation of particles through the nanopores. From this, we came up with back-side polymer-coated chip designs and demonstrated improved pore sensor temporal resolution by developing a nanopore with a thick polymethyl-methacrylate layer laminated on the bottom surface. The present findings may be useful in developing integrated solid-state nanopore sensors with embedded nanochannels and nanoelectrodes.
  • 2.

    【2hr】Photoluminescence and Electrochemiluminescence Dual-SignalingSensors for Selective Detection of Cysteine Based on Iridium(III)Complexes

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    机译 光致发光和电化学致发光双信号基于铱（III）的半胱氨酸选择性检测传感器复合体
    摘要：Cysteine (Cys) is important in biosynthesis, detoxification, and metabolism. The selective detection of Cys over structurally similar homocysteine (Hcy) or glutathione (GSH) remains an immense challenge. Although there are many methods for detecting Cys, photoluminescence (PL) and electrochemiluminescence (ECL) techniques are well-suited for clinical diagnostics and analytical technology because of their high sensitivities. Herein, we report PL and ECL dual-channel sensors using cyclometalated iridium(III) complexes for the discrimination of Cys from Hcy and GSH. The sensors react with cysteine preferentially because of kinetic differences in intramolecular conjugate addition/cyclization, enabling phosphorescence enhancement and ECL decrease in the blue-shifted region. Sensor 1 shows ratiometric PL turn-on and ECL turn-off for Cys. In addition, unique ECL-enhancing behavior of sensor 1 toward GSH enables discrimination between Cys and GSH. Sensor 1 was successfully applied to the detection of Cys in human serum by the ECL method. We demonstrate the first case of a Cys-selective PL and ECL dual-channel chemodosimetric sensor based on cyclometalated iridium(III) complexes and expect that the rational design of efficientPL and ECL dual-channel sensors will be useful in diagnostic technology.
  • 3.

    【2hr】Small-Molecule Poly(ADP-ribose) Polymerase and PD-L1 Inhibitor Conjugates as Dual-ActionAnticancer Agents

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    机译 小分子聚（ADP-核糖）聚合酶和PD-L1抑制剂共轭双作用。抗癌药
    摘要：Immune checkpoint blockades have revolutionized the treatment landscape for several cancer indications, yet they have not gained traction in a range of other tumors such as triple-negative breast cancer. Despite durable disease control by many patients, a third of cancer patients relapse due to acquired resistance. Combined immunotherapy has shown significant promise to overcome these grand challenges. In this report, we describe the synthesis and characterization of dual-action small-molecule PARP1/PD-L1 inhibitor conjugates as potential targeted anticancer agents. These conjugates display significant apoptosis and cytotoxic efficacy to approximately 2–20-fold better than their individual agents in a panel of cancer cell lines. This was underscored by derived combination indices, which was consistent with strong synergy when cells were treated with the individual agents, olaparib and BMS-001 using the Chou–Talalay method. Furthermore, we sought to unravel the mechanistic behavior of the conjugates and their implications on the PARP/PD-L1 axis. We used apoptosis, cellcycle, immunoblotting, and T-cell proliferation assays to establishthe synergy imparted by these conjugates. These multifunctional compoundsenable the discovery of small-molecule immunochemotherapeutic agentsand chemical probes to elucidate the cross-talk between DNA repairand PD-L1 pathways.
  • 4.

    【2hr】Disposable Colorimetric Paper-Based Probe for theDetection of Amine-Containing Gases in Aquatic Sediments

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    机译 一次性比色纸基探针水生沉积物中含胺气体的检测
    摘要：Amine compounds are considered highly important in environmental pollution, industrial, and medicinal fields. The objective of this work was to develop a disposable, highly accurate, highly selective, and low-cost paper-based probe through the combination of color change of seven pH indicators for the detection of amine compounds in the gaseous state. The probe was designed with seven rings which were printed using the wax-printing technique and colored with different pH indicators. The colors of the probe were analyzed using red, green, and blue (RGB) values extracted from the images obtained with a homemade smartphone application. The chemometric tools, principal component analysis, and hierarchical cluster analysis methods were adapted to further classify amine gases. The colorimetric probe showed an excellent capability for detecting the amines with high accuracy, prompt response, and high selectivity. These dye arrays have been proven to detect ethanolamine (NH2CH2CH2OH), dimethylamine ((CH3)2NH), and trimethylamine ((CH3)3N) gases at parts per million scale.
  • 5.

    【2hr】Magnetic, Pseudocapacitive, and H2O2-ElectrosensingProperties of Self-Assembled SuperparamagneticCo0.3Zn0.7Fe2O4 with EnhancedSaturation Magnetization

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    机译 磁性，伪电容和H2O2电化学自组装超顺磁性的性质具有增强作用的Co0.3Zn0.7Fe2O4饱和磁化
    摘要：The present work explores the structural, microstructural, optical, magnetic, and hyperfine properties of Co0.3Zn0.7Fe2O4 microspheres, which have been synthesized by a novel template-free solvothermal method. Powder X-ray diffraction, electron microscopic, and Fourier transform infrared spectroscopic techniques were employed to thoroughly investigate the structural and microstructural properties of Co0.3Zn0.7Fe2O4 microspheres. The results revealed that the microspheres (average diameter ∼121 nm) have been formed by self-assembly of nanoparticles with an average particle size of ∼12 nm. UV–vis diffuse reflectance spectroscopic and photoluminescence studies have been performed to study the optical properties of the sample. The studies indicate that Co0.3Zn0.7Fe2O4 microspheres exhibit a lower band gap value and enhanced PL intensity compared to their nanoparticle counterpart. The outcomes of dc magnetic measurement and Mössbauer spectroscopic study confirm that the sample is ferrimagnetic in nature. The values of saturation magnetization are 76 and 116 emu g–1 at 300 and 5 K, respectively,which are substantially larger than its nanosized counterpart. Theinfield Mössbauer spectroscopic study and Rietveld analysisof the PXRD pattern reveal that Fe3+ ions have migratedfrom [B] to (A) sites resulting in the cation distribution: (Zn2+0.46Fe3+0.54)A[Zn2+0.24Co2+0.3Fe3+1.46]BO4. Comparison ofelectrochemical performance of the Co0.3Zn0.7Fe2O4 microspheres to that of the Co0.3Zn0.7Fe2O4 nanoparticles revealsthat the former displays greater specific capacitance (149.13 F g–1) than the latter (80.06 F g–1)due to its self-assembled porous structure. Moreover, it was foundthat Co0.3Zn0.7Fe2O4 microspherespossess a better electrochemical response toward H2O2 sensing than Co0.3Zn0.7Fe2O4 nanoparticles in a wide linear range.
  • 6.

    【2hr】Studies of Ultrafast Transient Absorption Spectroscopyof Gold Nanorods in an Aqueous Solution

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    机译 超快速瞬态吸收光谱研究水溶液中纳米金棒的制备
    摘要：Herein, ultrafast transient absorption spectroscopy is performed to probe the electron transfer studies between aqueous solution and gold nanorods (Au NRs). The seed-mediated growth method is used to synthesize crystalline cylindrical Au NRs having longitudinal plasmon resonance peak maximum at 825 nm. The as-synthesized Au NRs show average width and length of ∼10 ± 2 and ∼50 ± 2 nm, respectively, with an aspect ratio in the range of ∼5. The time-resolved decay profiles have been studied in a subpicosecond resolution range using pump wavelength at 410 nm excitation and probe wavelengths from visible to near-infrared region. The plasmon dynamics studies of Au NRs depend on the electron heating phenomena, coherent acoustic phonon vibration and electronic transient behavior, i.e., electron–phonon coupling, and homogenous dephasing processes. Thus, the obtained results highlighted that the ultrafast charge transfer dynamics studies in Au NRs could play an important role to elucidate their electronic, photothermal, and optical properties for molecularimaging, photothermal therapy, and optoelectronic and light-harvestingdevices.
  • 7.

    【2hr】Mussel-Inspired Cell/Tissue-Adhesive, Hemostatic Hydrogelsfor Tissue Engineering Applications

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    机译 贻贝启发的细胞/组织粘合止血水凝胶用于组织工程应用
    摘要：The combination of multiple physiological (swelling, porosity, mechanical, and biodegradation) and biological (cell/tissue-adhesive, cell proliferation, and hemostatic) properties on a single hydrogel has great potential for skin tissue engineering. Adhesive hydrogels based on polydopamine (PDA) have become the most popular in the biomedical field; however, integrating multiple properties on a single adhesive hydrogel remains a challenge. Here, inspired by the chemistry of mussels, we developed PDA–sodium alginate–polyacrylamide (PDA–SA–PAM)-based hydrogels with multiple physiological and biological properties for skin tissue engineering applications. The hydrogels were prepared by alkali-induced polymerization of DA followed by complexation with SA in PAM networks. The chemical composition of the hydrogels was characterized by X-ray photoelectron spectroscopy. PDA–SA complexed chains were homogeneously dispersed in the PAM network and exhibited good elasticity and excellent mechanical properties, such as a compressive stress of 0.24 MPa at a compression strain of 70% for 0.4PDA–SA–PAM.The adhesive hydrogel also maintained a highly interconnected porousstructure (∼94% porosity) along with PDA microfibrils. Thehydrogel possesses outstanding swelling and biodegradability properties.Owing to the presence of the PDA–SA complex in the PAM network,the hydrogels show good adhesion to various substrates (plastic, skin,glass, computer screens, and leaves); for example, the adhesive strengthof the 0.4PDA–SA–PAM to porcine skin was 24.5 kPa. Theadhesive component of the PDA–SA chains in the PAM networksignificantly improves the cell proliferation, cell attachment, cellspreading, and functional expression of human skin fibroblasts (CCD-986sk)and keratinocytes. Moreover, the PDA chains exhibited good hemostaticproperties, resulting in rapid blood coagulation. Considering theirexcellent cell affinity, and rapid blood coagulation ability, thesemussel-inspired hydrogels have substantial potential for skin tissueengineering applications.
  • 8.

    【2hr】Cell-Derived Vesicles for in Vitro and in Vivo TargetedTherapeutic Delivery

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    机译 体外和体内靶向细胞衍生的囊泡治疗性递送
    摘要：Efficient delivery of therapeutics across the cell membrane to the interior of the cell remains a challenge both in vitro and in vivo. Here, we demonstrate that vesicles derived from cellular membranes can be efficiently loaded with cargo that can then be delivered to the interior of the cell. These vesicles demonstrated cell-targeting specificity as well as the ability to deliver a wide range of different cargos. We utilized this approach to deliver both lipophilic and hydrophilic cargos including therapeutics and DNA in vitro. We further demonstrated in vivo targeting and delivery using fluorescently labeled vesicles to target tumor xenografts in an animal. Cell-derived vesicles can be generated in high yields and are easily loaded with a variety of cargos. The ability of these vesicles to specifically target the same cell type from which they originated provides an efficient means of delivering cargo, such as therapeutics, both in vitro and in vivo.
  • 9.

    【2hr】Nanocellular Foaming Behaviors of Chain-ExtendedPoly(lactic acid) Induced by Isothermal Crystallization

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    机译 扩链的纳米孔泡沫行为等温结晶诱导的聚乳酸
    摘要：Recently, the fabrication of semicrystalline polymer foams with a nanocellular structure by supercritical fluids has been becoming a newly developing research hotspot, owing to their peculiar properties and prospective applications. In this work, a facile and effective isothermal crystallization-induced method was proposed to prepare nanocellular semicrystalline poly(lactic acid) (PLA) foams using CO2 as a physical blowing agent. Styrene–acrylonitrile–glycidyl methacrylate (SAG) as a chain extender (CE) was introduced into PLA through a melt-mixing method to improve the crystallization behavior and melt viscoelasticity of PLA. The chain extension reaction between PLA and SAG occurred successfully as well as the branching and micro cross-linking structures were generated in chain-extended PLA (CPLA) samples, which were confirmed by Fourier transform infrared spectra, gel fraction, and intrinsic viscosity measurements. Owing to the nucleation effect of branching points and the restricted movement of PLA molecular chains by the formation of branching and/or microcross-linking structures, a large number of small spherocrystals were generated in CPLA samples,which was beneficial to produce nanocells. Nanocellular CPLA foamswere prepared successfully, when the foaming temperature was 125 °C.As the SAG content increased, the cell size of various PLA foams decreasedfrom 364 ± 198 to 249 ± 100 nm and their volume expansionratio increased from 1.15 ± 0.05 to 2.22 ± 0.01 times, gradually.When the foaming temperature increased from 125 to 127 °C, aninteresting transition from nanocells to microcells could be observedin CPLA foam with the CE content of 2 wt %. Finally, the formationmechanism of nanocells in various PLA foams was proposed and clarifiedusing a schematic diagram.
  • 10.

    【2hr】Thermal Processing of Chloride-Contaminated PlutoniumDioxide

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    机译 氯化物污染P的热处理二氧化物
    摘要：Over 80 heat treatment experiments have been made on samples of chloride-contaminated plutonium dioxide retrieved from two packages in storage at Sellafield. These packages dated from 1974 and 1980 and were produced in a batch process by conversion of plutonium oxalate in a furnace at around 550 °C. The storage package contained a poly(vinyl chloride) (PVC) bag between the screw top inner and outer metal cans. Degradation of the PVC has led to adsorption of hydrogen chloride together with other atmospheric gases onto the PuO2 surface. Analysis by caustic leaching and ion chromatography gave chloride contents of ∼2000 to >5000 ppm Cl (i.e., μgCl g–1 of the original sample). Although there are some subtle differences, in general, there is surprisingly good agreement in results from heat treatment experiments for all the samples from both cans. Mass loss on heating (LOH) plateaus at nearly 3 wt % above 700 °C, although samples that were long stored under an air atmosphere or preexposed to 95% relative humidity atmospheres, gave higher LOH up to ∼4 wt %. The majority of the mass loss is due to adsorbedwater and other atmospheric gases rather than chloride. Heating volatilizeschloride only above ∼400 °C implying that simple physisorptionof HCl is not the main cause of contamination. Interestingly, above700 °C, >100% of the initial leachable chloride can be volatilized.Surface (leachable) chloride decreases quickly with heat treatmenttemperatures up to ∼600 °C but only slowly above thistemperature. Storage in air atmosphere post-heat treatment apparentlyleads to a reequilibration as leachable chloride increases. The presenceof a “nonleachable” form of chloride was thus inferredand subsequently confirmed in PuO2 samples (pre- and post-heattreatment) that were fully dissolved and analyzed for the total chlorideinventory. Reheating samples in either air or argon at temperaturesup to the first heat treatment temperature did not volatilize significantamounts of additional chloride. With regard to a thermal stabilizationprocess, heat treatment in flowing air at 800 °C with coolingand packaging under dry argon appears optimal, particularly, if thinnerpowder beds can be maintained. From electron microscopy, heat treatmentappeared to have the most effect on degrading the square plateletparticles compared to those with the trapezoidal morphology.
  • 11.

    【2hr】Computational Peptidology Assisted by Conceptual DensityFunctional Theory for the Study of Five New Antifungal Tripeptides

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    机译 概念密度辅助的计算肽学研究五种新型抗真菌三肽的功能理论
    摘要：A well-behaved model chemistry previously validated for the study of the chemical reactivity of peptides was considered for the calculation of the molecular properties and structures of a group of five new antifungal tripeptides, namely (2R)-2-[(2S)-2-[(2S)-2-amino-3-phenylpropanamido]propanamido]-5-[(diaminomethylidene)amino]pentanoic acid, (2S)-2-[(2S)-2-[(2S)-2-amino-3-phenyl propanamido]propanamido]-3-(4-hydroxyphenyl)propanoic acid, (2S)-2-[(2S)-2-[(2S)-2-amino-3-phenylpropanamido]-3-methylbutanamido]-3-(4-hydroxyphenyl)propanoic acid, (2R)-2-[(2S)-2-[(2S)-2-amino-3-phenylpropanamido]-3-(1H-indol-3-yl)propanamido]-3-sulfanylpropanoic acid, and (2S)-2-[(2S)-2-[(2S)-2-amino-3-phenylpropanamido]-3-(1H-indol-3-yl)propanamido]-3-(4-hydroxyphenyl)propanoic acid, according to their amino acid sequences. A methodology based on conceptual density functional theory was chosen for the determination of the reactivity descriptors. The molecular active sites were associated with the active regions of the molecules that were associated with the nucleophilic, electrophilic, and radical Fukui functions. Additionally, the pKa values for the different peptides are predicted with great accuracy, which constitutes a useful knowledge for the process of drug design. Finally, the bioactivity scores forthe new antifungal peptides are predicted through a homology methodologyrelating them with the calculated reactivity descriptors.
  • 12.

    【2hr】Graphitic Carbon Nitride Nanosheets Covalently Functionalizedwith Biocompatible Vitamin B1: Synthesis, Characterization,and Its Superior Performance for Synthesis of Quinoxalines

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    机译 石墨碳氮化物纳米片共价功能化与生物相容性维生素B1的合成，表征，及其合成喹喔啉的优异性能
    摘要：The physical properties of two-dimensional nanosheet materials make them promising candidates as active materials in the areas of photoelectronics, fuel cells, sensors, water splitting, solar energy conversion, CO2 reduction, and heterogeneous catalysis. Among two-dimensional nanosheet materials, graphitic carbon nitride due to its electronic structure and high chemical and thermal stability possesses unique properties. Covalent functionalization of graphitic carbon nitride could be the key step in modifying its ability and significantly improving its properties. To this purpose, a novel strategy for the covalent functionalization of g-C3N4 nanosheets (CN) with vitamin B1 (VB1) by using 1,3-dibromopropane as a covalent linker for the first time is demonstrated. The obtained CN-Pr-VB1 exhibits increased thermal stability compared to the VB1 which is important in the practice application and can be easily dispersed in common organic solvents. The efficacy of the CN-Pr-VB1 as a heterogeneous organocatalyst was evaluated in the quinoxaline synthesis under solvent-free conditionsand afforded good isolated yield with high purity. Moreover, the preparedcatalyst could be facilely recycled and reused for seven consecutivecycles without a noticeable decrease in the catalytic activity. Extensivecharacterization confirmed the stability of morphology and chemicalstructure after recyclability of the CN-Pr-VB1.
  • 13.

    【2hr】Study on the Interaction between Galena and SphaleriteDuring Grinding Based on the Migration of Surface Components

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    机译 方铅矿与闪锌矿相互作用的研究基于表面成分迁移的磨削过程
    摘要：In Pb–Zn ore flotation, unintentional activation of sphalerite often leads to difficult separation of Pb and Zn minerals, during which grinding plays a key role in unintentional activation. Therefore, the aim of this study was to evaluate the surface component changes of two different mineral particles and to propose the interaction between galena and sphalerite during mixed grinding using time-of-flight secondary ion mass spectrometry (ToF-SIMS). The results show that after mixed grinding of the galena and sphalerite, the Pb content on the sphalerite surface increased with the decrease of Zn and Fe contents on the sphalerite surface. The lead ions from galena were obviously absorbed onto the sphalerite surface, while the zinc and iron ions from sphalerite were not obviously migrated to the galena surface. Principal component analysis (PCA) of a dataset composed of 206 positive ion peaks of galena and sphalerite indicates that the surface components of galena and sphalerite migrated from either side to different degrees. This study successfully identified an importantfactor for unintentional activation of lead and zinc minerals duringflotation: homogenization of surface components of different mineralsduring grinding.
  • 14.

    【2hr】Synthesis and Properties of UV-CurablePolyfunctional Polyurethane Acrylate Resins from Cardanol

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    机译 紫外光固化的合成与性能腰果酚的多官能聚氨酯丙烯酸酯树脂
    摘要：A novel UV-curable polyurethane acrylate (PUA) oligomer was synthesized by modifying cardanol with a polyfunctional acrylate precursor obtained through reacting pentaerythritol triacrylate with isophoronediisocyanate. Chemical structures of the obtained cardanol-based PUA (C-PUA) oligomer were confirmed by Fourier transform infrared and 1H NMR. Subsequently, viscosity and gel content of the C-PUA resins containing different quantities of hydroxymethyl methacrylate (HEMA) were characterized. The C-PUA oligomer possessed a viscosity of 8360 mPa s, which reduced to 115 mPa s when 40% of the HEMA diluent was added. Furthermore, thermal, mechanical, coating, and swelling properties of the resulting UV-cured C-PUA/HEMA materials were investigated. The ultimate biomaterials showed excellent performance, including a glass transition temperature (Tg) of 74–123 °C, maximum thermal degradation temperature of 437–441 °C, tensile strength of 12.4–32.0 MPa, tensile modulus of 107.2–782.7 MPa, and coating adhesion of 1–2. In conclusion, the developed C-PUA resins show great potential to be applied in UV-curable materials like coatings.
  • 15.

    【2hr】Tuning the Catalytic Activity of PdxNiy (x + y = 6) Bimetallic Clusters for Hydrogen Dissociative Chemisorptionand Desorption

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    机译 调整PdxNiy（x + y = 6）双金属簇对氢解离化学吸附的催化活性和解吸
    摘要：Density functional theory was used to study dissociative chemisorption and desorption on PdxNiy (x + y = 6) bimetallic clusters. The H2 dissociative chemisorption energies and the H desorption energies at full H saturation were computed. It was found that bimetallic clusters tend to have higher chemisorption energy than pure clusters, and the capacity of Pd3Ni3 and Pd2Ni4 clusters to adsorb H atoms is substantially higher than that of other clusters. The H desorption energies of Pd3Ni3 and Pd2Ni4 are also lower than that of the Pd6 cluster and comparable to that of the Ni6 cluster, indicating that it is easier to pull the H atom out of these bimetallic catalysts. This suggests that the catalytic efficiency for specific PdxNiy bimetallic clusters may be superior to bare Ni or Pd clusters and that it may be possible to tune bimetallic nanoparticles to obtain better catalytic performance.
  • 16.

    【2hr】Click Chemistry in the Design and Production of HybridTracers

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    机译 单击化学在杂种的设计和生产中示踪剂
    摘要：Hybrid tracers containing both fluorescent and radioactive imaging labels have demonstrated clinical potential during sentinel lymph node procedures. To combine these two labels on a single targeting vector that allows tumor-targeted imaging, end-labeling strategies are often applied. For αvβ3-integrin-targeting hybrid tracers, providing an excellent model for evaluating tracer development strategies, end-labeling-based synthesis provides a rather cumbersome synthesis strategy. Hence, the aim of this study was to investigate the use of heterobifunctional cyanine dyes in a click-chemistry-based synthesis strategy for RGD-based hybrid tracers. The triazole-based hybrid tracers DTPA.DBCO.N3(SO3)-Cy5-c[RGDyK] and DTPA.BCN.N3(SO3)-Cy5-c[RGDyK] were obtained in fewer steps than DTPA-Lys(Cy5(SO3)methyl)-Cys-c[RGDyK] and had partition coefficients of log P(o/w) = −2.55 ± 0.10, −1.45 ± 0.03, and −2.67 ± 0.12, respectively. Both tracers were chemically stable, and the brightnesses of DTPA.DBCO.N3(SO3)-Cy5-c[RGDyK] and DTPA.BCN.N3(SO3)-Cy5-c[RGDyK] were, respectively, 23 × 103 and 40 × 103 M–1 cm–1; lower than that of the reference tracer DTPA-Lys(Cy5(SO3)methyl)-Cys-c[RGDyK] (50 × 103 M–1 cm–1). Assessment of serum protein binding revealed no statistically significant difference (44 ± 2 and 40 ± 2% bound for DTPA.DBCO.N3(SO3)-Cy5-c[RGDyK] and DTPA.BCN.N3(SO3)-Cy5-c[RGDyK], respectively; 36 ± 5% bound for DTPA-Lys(Cy5(SO3)methyl)-Cys-c[RGDyK]; p > 0.05). DTPA.DBCO.N3(SO3)-Cy5-c[RGDyK] (KD = 17.5 ± 6.0) had a statistically significantly higher affinity than the reference compound DTPA-Lys(Cy5(SO3)methyl)-Cys-c[RGDyK] (KD = 30.3 ± 5.7; p <0.0001), but DTPA.BCN.N3(SO3)-Cy5-c[RGDyK] hada statistically significantly lower affinity (KD = 76.5 ± 18.3 nM; p < 0.0001).Both [111In]DTPA.DBCO.N3(SO3)-Cy5-c[RGDyK] and [111In]DTPA.BCN.N3(SO3)-Cy5-c[RGDyK] enabled in vivovisualization of the 4T1 tumor via fluorescence and single-photonemission computed tomography (SPECT) imaging. Biodistribution data(% ID/g) revealed a significant increase in nonspecific uptake inthe kidney, liver, and muscle for both [111In]DTPA.DBCO.N3(SO3)-Cy5-c[RGDyK] and [111In]DTPA.BCN.N3(SO3)-Cy5-c[RGDyK]. As a result of the higher background activity, the tumor-to-backgroundratio of the click-labeled RGD analogues was twofold lower comparedto the end-labeled reference compound. The use of click chemistry labelingdid not yield a pronounced negative effect on serum protein binding,in vitro stability, and receptor affinity; and tumors could stillbe visualized using SPECT and fluorescence imaging. However, quantitativein vivo biodistribution data suggest that the triazole and strainedcyclooctyne moieties associated with this type of click chemistrynegatively influence the pharmacokinetics of RGD peptides. Nevertheless,the design might still hold promise for other targets/targeting moieties.
  • 17.

    【2hr】64Cu-Labeled Ubiquitin for PET Imagingof CXCR4 Expression in Mouse Breast Tumor

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    机译 用于PET成像的64Cu标签泛素乳腺肿瘤中CXCR4表达的表达
    摘要：Ubiquitin has been recently identified as a chemokine receptor 4 (CXCR4) natural ligand, offering great potential for positron emission computed tomography (PET) imaging of CXCR4 expression. This study reports the preparation and evaluation of (64Cu)-radiolabeled ubiquitin for CXCR4 imaging. The ubiquitin was first fused with a C-terminal GGCGG sequence, and the resulting recombinant ubiquitin derivative UbCG4 was then functionalized with the trans-cyclooctene (TCO) moiety via thiol–maleimide click reaction, followed by 64Cu-radiolabeling through the TCO/Tz (tetrazine)-based Diels–Alder click reaction. In the prepared in vitro studies, the prepared (64Cu)-UbCG4 showed significantly higher specific uptakes in the 4T1 breast cancer cells compared with the uptakes in the CXCR4-knockdown 4T1 cells. In the in vivo evaluation in the 4T1-xenograft mouse model, (64Cu)-UbCG4 demonstrated a similar tumor uptake but much lower backgrounds compared with 64Cu-labeled AMD3465. These results suggested that (64Cu)-UbCG4 could serve as a potent PET tracer for the noninvasive imaging of CXCR4expression in tumors.
  • 18.

    【2hr】Star-Shaped ESIPT-Active Mechanoresponsive LuminescentAIEgen and Its On–Off–On Emissive Response to Cu2+/S2–

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    机译 星形ESIPT-主动机械响应发光AIEgen及其对Cu2 + / S2-的开-关-开发射响应
    摘要：Design and development of multifunctional materials have drawn incredible attraction in recent years. Herein, we report the design and construction of versatile star-shaped intramolecular charge transfer (ICT)-coupled excited-state intramolecular proton transfer (ESIPT)-active mechanoresponsive and aggregation-induced emissive (AIE) luminogen triaminoguanidine-diethylaminophenol (LH3) conjugate from simple precursors triaminoguanidine hydrochloride and 4-(N,N-diethylamino)salicylaldehyde. Solvent-dependent dual emission in nonpolar to polar protic solvents implies the presence of ICT-coupled ESIPT features in the excited state. Aggregation-enhanced emissive feature of LH3 was established in the CH3CN/water mixture. Furthermore, this compound exhibits mechanochromic fluorescence behavior upon external grinding. Fluorescence microscopy images of pristine, crystal, and crushed crystals confirm the naked-eye mechanoresponsive characteristics of LH3. In addition, LH3 selectively sensed a Cu2+ ion through a colorimetric and fluorescence “turn-off” route, and subsequently,the LH3-Cu2+ ensemble could actas a selective and sensitive sensor for S2– in a“turn-on” fluorescence manner via a metal displacementapproach. Reversible “turn-off–turn-on” featuresof LH3 with Cu2+/S2– ions were efficiently demonstrated to construct the IMPLICATIONlogic gate function. The Cu2+/S2–-responsivesensing behavior of LH3 was established inthe paper strip experiment also, which can easily be characterizedby the naked eye under daylight as well as a UV lamp (λ = 365nm).
  • 19.

    【2hr】Engineering of Gadolinium-Decorated Graphene OxideNanosheets for Multimodal Bioimaging and Drug Delivery

    包量

    机译 d装饰氧化石墨烯的工程用于多峰生物成像和药物递送的纳米片
    摘要：Engineering of water-dispersible Gd3+ ions-decorated reduced graphene oxide (Gd-rGO) nanosheets (NSs) has been performed. The multifunctional capability of the sample was studied as a novel contrast agent for swept source optical coherence tomography and magnetic resonance imaging, and also as an efficient drug-delivery nanovehicle. The synthesized samples were fabricated in a chemically stable condition, and efforts have been put toward improving its biocompatibility by functionalizing with carbohydrates molecules. Gd incorporation in rGO matrix enhanced the fluorouracil (5-FU) drug loading capacity by 34%. The release of the drug was ∼92% within 72 h. Gd-rGO nanosheets showed significant contrast in comparison to optically responsive bare GO for swept source optical coherence tomography. The longitudinal relaxivity rate (r1) of 16.85 mM–1 s–1 for Gd-rGO was recorded, which was 4 times larger than that of the commercially used clinical contrast agent Magnevist (4 mM–1 s–1) at a magnetic field strength of 1.5 T.
  • 20.

    【2hr】Improved Current Extraction of Cu/Si Nanowire Heterojunctionsfor Self-Powered Photodetecting with Insertion of MoOx Quantum Dots Film

    包量

    机译 改进的Cu / Si纳米线异质结电流提取MoOx量子点薄膜的自供电光电检测技术
    摘要：MoOx quantum dots were inserted between the Si nanowires (SiNWs) and Cu contacts to form the MoOx/SiNW heterojunctions via the low-temperature solution process. The common Schottky heterojunction of Cu/SiNWs is used as the referred device, and the photoelectric characteristics of Cu/MoOx/Si structures are detailedly investigated. The results indicate that the inset of MoOx between Cu and SiNWs obviously enhances photoelectric conversion efficiency from 1.58 to 3.92%, and photodetection characteristics have also improved compared to the referred device. We attribute these experimental findings to the fact that the incorporation of MoOx quantum dots into the Cu/Si heterojunction could enhance the transport of holes and inhibit the injection of electrons from Si into the top Cu electrode. In addition, it is believed that such an improved performance also comes from the improved optical absorption as well as the optimized carrier transfer and collection capability of MoOx/SiNW radial heterojunctions.
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