Monitoring and Quantifying the Passive Transport of Molecules Through Patch–Clamp Suspended Real and Model Cell Membranes

Transport of active molecules across biological membranes is a central issue for the success of many pharmaceutical strategies. Herein, we combine the patch–clamp principle with amperometric detection for monitoring fluxes of redox‐tagged molecular species across a suspended membrane patched from a macrophage. Solvent‐ and protein‐free lipid bilayers (DPhPC, DOPC, DOPG) patched from single‐wall GUV have been thoroughly investigated and the corresponding fluxes measurements quantified. The quality of the patches and their proper sealing were successfully characterized by electrochemical impedance spectroscopy. This procedure appears versatile and perfectly adequate to allow the investigation of transport and quantification of the transport properties through direct measurement of the coefficients of partition and diffusion of the compound in the membrane, thus offering insight on such important biological and pharmacological issues.     

Metal‐Free Aminosulfonylation of Aryldiazonium Tetrafluoroborates with DABCO⋅(SO2)2 and Hydrazines

The coupling of aryldiazonium tetrafluoroborates, DABCO?(SO₂)₂, and hydrazines under metal‐free conditions leads to the formation of aryl N‐aminosulfonamides. The reaction proceeds smoothly at room temperature and shows broad functional‐group tolerance. A radical process is proposed for this transformation.     

Copper‐Catalyzed One‐Pot Denitrogenative–Dehydrogenative–Decarboxylative Coupling of β‐Ketoacids with Trifluorodiazoethane: Facile Access to Trifluoromethylated Aldol Products

A novel copper‐catalyzed one‐pot cross‐coupling of β‐ketoacids with in situ generated trifluorodiazoethane has been developed. This reaction provides a direct and efficient method, in which one C?C bond and one C?O bond were formed in a carbenoid center with concomitant denitrogenation–dehydrogenation–decarboxylation, to afford trifluoromethylated aldol products. In several preliminary experiments, good to high enantioselectivities were also obtained.     

Asymmetrically superhydrophobic cotton fabrics fabricated by mist polymerization of lauryl methacrylate

A graft-polymerization process with atomized lauryl methacrylate as monomer is used to fabricate fluorine-less and asymmetrically superhydrophobic cotton fabrics. The polymers synthesized in the process can form nanoscale hierarchical structures on the cotton surface, and the surface morphology can be controlled by choosing a suitable solvent or by varying the feeding quantity of the monomer mist stream. After applying the surface modification to cotton fabrics, an asymmetrically superhydrophobic surface is achieved without any additional nanosized particles, and the solvent damages on the cotton fabrics are controllable at a very low level. Surface characterization reveals that the modified side of the cotton fabric has laundering-durable and mechanically stable superhydrophobicity with a water contact angle of more than 150°, whereas the opposite inherits the hydrophilic property of pristine cotton fabric. The modified cotton fabrics are found to have medium-level water-absorbing ability between pristine cotton and PET fabrics, as well as good vapor transmissibility similar to pristine cotton fabric. These properties are of great significance in textile and medical applications.     

聚阳离子糖缀物氢键诱导TPPS手性聚集

利用原子转移自由基聚合(ATRP)方法制备了亲水性嵌段聚合物聚乙二醇-b-聚甲基丙烯酸N,N-二甲氨基乙酯(PEG-b-PDMAEMA),并通过季铵化反应,得到侧链接枝不同单糖分子(葡萄糖、半乳糖、甘露糖)的聚阳离子糖缀物PEG-b-P(DMAEMA-co-DMAEMA-Sac)(Monosaccharide).研究了该聚合物与5,10,15,20-四(对磺酸基苯基)-卟啉(TPPS)在水溶液中的复合自组装行为.研究结果表明,TPPS在该组装体中以J-聚集体形式存在且显示超分子手性特征.手性信号的产生是聚合物侧链糖单元C(4)和C(5)上的羟基与TPPS通过非共价键——氢键相互作用的结果,因此手性信号方向应与糖单元构型有关.通过对比单糖构型发现,具有(4S,5R)构型的糖单元可诱导TPPS产生424 nm正Cotton效应和490 nm负Cotton效应的聚集体,具有(4R,5R)构型的糖单元可诱导TPPS产生424 nm负Cotton效应和490 nm正Cotton效应的聚集体.     

Graphene oxide assisted facile hydrothermal synthesis of LiMn0.6Fe0.4PO4 nanoparticles as cathode material for lithium ion battery

Assisted by graphene oxide（GO）,nano-sized LiMn0.6Fe0.4PO4 with excellent electrochemical performance was prepared by a facile hydrothermal method as cathode material for lithium ion battery.SEM and TEM images indicate that the particle size of LiMn0.6Fe0.4PO4（S2）was about 80 nm in diameter.The discharge capacity of LiMn0.6Fe0.4PO4 nanoparticles was 140.3 mAh-g^1 in the first cycle.It showed that graphene oxide was able to restrict the growth of LiMn0.6Fe0.4PO4 and it in situ reduction of GO could improve the electrical conductivity of LiMn0.6Fe0.4PO4 material.     

液相色谱-串联质谱法同时检测DNA中3-甲基腺嘌呤和3-乙基腺嘌呤

利用阳离子交换固相萃取柱(Waters Oasis MCX)富集净化DNA样品,建立了液相色谱串联质谱(LC-MS/MS)同时检测DNA中3-甲基腺嘌呤(N3-MeA)和3-乙基腺嘌呤(N3-EtA)的方法。采用氘代-3-甲基腺嘌呤(d3-N3-MeA)和氘代-3-乙基腺嘌呤(d5-N3-EtA)为内标;进样量3μL,分析时间为13 min;亲水相互作用色谱柱(Waters XBridge HILIC)进行液相分离,流动相为10 mmol/L甲酸铵-乙腈溶液(5∶95,V/V,pH=4.0),流速250μL/min;质谱条件:电喷雾离子源,多反应监测正离子扫描方式;电喷雾电压:5500 V,雾化气:369 Pa,气帘气:185 Pa,电离温度:400℃,驻留时间:40 ms。本方法对N3-MeA和N3-EtA的检出限分别为0.043和0.007μg/L,方法回收率为87.8%~103.0%。采用本方法检测了卷烟烟气粒相物暴露的DNA中N3-MeA和N3-EtA含量。结果表明,卷烟烟气粒相物暴露后的小牛胸腺DNA中3-甲基腺嘌呤和3-乙基腺嘌呤可被本方法定量检出。     

A Simplified Global Model to Describe the Oxidation of Acetylene Under Nanosecond Pulsed Discharges in a Complex Corona Reactor

The objective of this paper is to analyse the oxidation of acetylene under nanosecond pulsed N₂/O₂ discharges generated in a complex multi-pin-to-plane (MPP) corona reactor in the frame of Yan’s generic chemical kinetic model. We made use of the results obtained from the detailed kinetic model published previously (Redolfi et al. in Plasma Chem Plasma Process 29(3):173–195, 2009) in order to propose a global reactor models based on Yan’s generic chemical model and taking into account the non-homogeneous and non-stationary character of the discharges. This enables us expressing the energy cost in terms of physical and kinetic parameters of the discharge. We checked the model validity by comparing predicted and measured energy cost-values for acetylene in MPP reactor. The methodology presented may be adapted to predict the energy cost in other complex corona reactor provided the model parameters are determined experimentally.     

豆芽中甲硝唑、多菌灵、赤霉素、6-苄基腺嘌呤、2,4-二氯苯氧乙酸的定量检测

本文建立了快速筛查豆芽中常见添加物甲硝唑、多菌灵、赤霉素、6-苄基腺嘌呤和2,4-二氯苯氧乙酸的液相色谱定量方法。回收率为79%～96.6%,定量限在20～200μg/kg。对市场随机抽查64份豆芽样品检测发现,高达32份样品中含有1种以上添加物,主要是多菌灵、6-苄基腺嘌呤和2,4-二氯苯氧乙酸。