α-单取代环十二酮肟及缩氨基硫脲的合成及晶体结构

单晶X射线衍射分析表明, α-单取代环十二酮与氨衍生物羟胺和氨基硫脲发生缩合反应得到两种母体构象均为[3333], 而取代基为边外向或角反向的α-单取代环十二酮肟或缩氨基硫脲. 利用底物的“角位羰基参与反应”原理, “记忆效应”及进攻试剂与底物是否形成氢键解释了这一实验结果. 通常情况下, 试剂从空间障碍小的一面进攻羰基而生成α-角反取代环十二酮肟或缩氨基硫脲. 当试剂与底物的取代基之间能够形成分子间氢键时, 则生成α-边外取代环十二酮肟或缩氨基硫脲.     

PVC DISULFIDE AS CATHODE MATERIALS FOR SECONDARY LITHIUM BATTERIES

PVC disulfide (2SPVC) was synthesized by solution crosslink and its molecular structure was confirmed by infrared spectrum. 2SPVC's specific area is 36.1 m2·g-1 tested by stand BET method, and granularity experiment gives out the particle size of d0.5= 11.3μm. With SEM (Scanning Electron Microscope) experiment the surface morphology and particle shape of 2SPVC were observed. Cyclic voltammetry (scan rate: 0.5 mV·s-1) shows that 2SPVC experience an obvious S-S redox reaction in charge-discharge process. When 2SPVC was used as cathode material for secondary lithium battery in a 1 mol·L-1 solution of lithium bis(trifluoromethylsulfonyl) imide (Li(CF3SO2)2N) in a 5:45:50 volume ratio mixture of o-xylene (oxy), diglyme (DG) and dimethoxymethane (DME) at 30℃, the first discharge capacity of 2SPVC is about 400.3 mAh·g-1 which is very close to its theoretical value (410.5 mAh·g-1) at a constant discharge current of 15 mA·g-1. It can retain at about 346.1 mAh·g-1 of discharge capacity after 30 charge-discharge cycles. So 2SPVC is a very promising cathode candidate for rechargeable lithium batteries.     

One-step hexaplex immunoassays by on-line paper substrate-based electrospray ionization mass spectrometry for combined cancer biomarker screening

Mass spectrometry (MS) is attractive as a multiplexed immunoassay readout benefiting from its high sensitivity, speed and mass resolution. Here, a simple paper-based hexaplex immunoassay with an on-line MS readout was proposed, using functionalized paper as the immune substrates, along with rhodamine-based mass tags assembled on gold nanoparticles prepared as the mass probes (MPs). Simultaneous immune capture and labeling were conducted in one step on paper substrates in 96-well plates with a high throughput within 30 minutes, and the on-line efficient dissociation of the mass tags highly facilitated the hexaplex readout of the immune signals by a newly established on-line paper substrate-based electrospray ionization-MS setup. Six MPs were synthesized for the simultaneous quantification of six important cancer protein markers (cancer antigen 15-3, cancer antigen 19-9, carcinoma embryonic antigen, cancer antigen 125, human epididymis protein 4, and alpha fetoprotein) using only 10 μL serum, presenting satisfactory sensitivity, accuracy and specificity. This platform was further tested in screening for the six biomarkers in serum samples of patients with breast, liver and gastric cancers, showing its high potential for sensitive and specific early cancer diagnosis.

On-line paper substrate based electrospray ionization mass spectrometry for hexaplex immunoassays.     

Carbene-catalyzed enantioselective annulation of dinucleophilic hydrazones and bromoenals for access to aryl-dihydropyridazinones and related drugs

4,5-Dihydropyridazinones bearing an aryl substituent at the C6-position are important motifs in drug molecules. Herein, we developed an efficient protocol to access aryl-dihydropyridazinone molecules via carbene-catalyzed asymmetric annulation between dinucleophilic arylidene hydrazones and bromoenals. Key steps in this reaction include polarity-inversion of aryl aldehyde-derived hydrazones followed by chemo-selective reaction with enal-derived α,β-unsaturated acyl azolium intermediates. The aryl-dihydropyridazinone products accessed by our protocol can be readily transformed into drugs and bioactive molecules.

Polarity inversion of arylidene hydrazones to react with bromoenals via carbene organic catalysis is disclosed. The reaction enantioselectively affords 6-aryl-4,5-dihydropyridazinones and related drugs with proven commercial applications.     

Tuning cell adhesion on gradient poly(2-hydroxyethyl methacrylate)-grafted surfaces

A simple yet versatile method was developed to prepare a low-density polymerization initiator gradient, which was combined with surface-initiated atom transfer radical polymerization (ATRP) to produce a well-defined poly(2-hydroxyethyl methacrylate) (HEMA) gradient substrate. A smooth variation in film thickness was measured across the gradient, ranging from 20 A to over 80 A, but we observed a nonmonotonic variation in water contact angle. Fits of X-ray reflectivity profiles suggested that at the low graft density end, the polymer chain structure was in a "mushroom" regime, while the polymer chains at high graft density were in a "brush" regime. It was found that the "mushroom" region of the gradient could be made adhesive to cells by adsorbing adhesion proteins, and cell adhesion could be tuned by controlling the density of the polymer grafts. Fibroblasts were seeded on gradients precoated with fibronectin to test cellular responses to this novel substrate, but it was found that cell adhesion did not follow the expected trend; instead, saturated cell adhesion and spreading was found at the low grafting density region.     

Sorption behavior of Co(II) on γ-Al<Subscript>2</Subscript>O<Subscript>3</Subscript> in the presence of humic acid

The fate and transport of toxic metal ions and radionuclides in the environment is generally controlled by sorption reactions. The extent of sorption of divalent metal cations is controlled by a number of factors including cosorbing or complexing. In this work, the effects of pH, humic acid HA/Co(II) addition orders, ionic strength, concentration of HA, and foreign cations on the Co(II) sorption on γ-Al₂O₃ in the presence of HA were investigated. The sorption isotherms of Co(II) on γ-Al₂O₃ in the absence and presence HA were also studied and described by using S-type sorption model. The experimental results showed that the Co(II) sorption is strongly dependent on the pH values, concentration of HA, but independent of HA/Co(II) addition orders, ionic strength, and foreign cations in the presence of HA under our experimental conditions. The results also indicated that HA enhanced the Co(II) sorption at low pH, but reduced the Co(II) sorption at high pH. It was hypothesized that the significantly positive influence of HA at low pH on the Co(II) sorption on γ-Al₂O₃ was attributed to strong surface binding of HA on γ-Al₂O₃ and subsequently the formation of ternary surface complexes such as ≡S-OOC-R-(COO⁻) _x Co^2−x . Chemi-complexation may be the main mechanism of the Co(II) sorption on γ-Al₂O₃ in the presence of HA.     

A membrane separation technique for optimizing sample preparation of MALDI-TOF MS detection

Here, we report a new method based on the combination of membrane separation technology and nanomaterial to rapid detection of peptides and protein with MALDI-TOF MS. This method shows advantages as it can inhibit the heterogeneous of sample spot and enhance the target molecular signal intensity.     

沉淀法高效制备聚多巴胺纳米粒子

为得到分散性和稳定性较好的聚多巴胺纳米粒子,利用“沉淀-再分散法”高效制备了聚多巴胺纳米粒子水分散液。 首先利用溶液氧化法制备了分散在水/乙醇中的聚多巴胺纳米粒子,然后向分散液中加入丙酮使聚多巴胺纳米粒子絮凝。 收集沉降物,用丙酮冲洗并干燥后,加水重新分散得到纯化的聚多巴胺纳米粒子水分散液。 丙酮沉淀法得到的聚多巴胺纳米粒子形貌规整,分散性好,粒径分布在250 nm左右,在水中具有良好的储存稳定性和光热性能,与传统的超速离心提纯法相比,产率可提高57.4%。 此方法为其之后在药物载体及光热治疗等方面的应用研究提供了便利。     

大孔吸附树脂对大豆皂苷的吸附研究

比较了5种大孔吸附树脂对大豆皂苷的吸附等温线、吸附容量、解吸率和吸附动力学。发现ZTC-1树脂对大豆皂苷吸附量大、解吸容易、吸附速度快，是一种良好的大豆皂苷吸附荆，AB-8树脂次之．选择ZTC-l树脂纯化大豆皂苷粗提液，得到大豆皂苷产品纯度为78．2％(干物质)，回收率为93．1％．     

聚1-氨基蒽醌在二次锂电池正极材料中的应用

采用化学方法合成聚1-氨基蒽醌并用于二次锂电池正极材料,通过红外光谱、扫描电镜、粒度测试、循环伏安以及充放电测试等方法对材料的官能团结构、微观形貌、颗粒大小以及电化学性能等进行了研究与分析.实验表明,与金属锂组成二次锂电池后,聚1-氨基蒽醌达到了218.3 mAh•g－1的首次放电容量,经过25次循环后仍可保持较高的充放电效率.由于材料具有较高的能量密度且不含对环境有污染的元素S,因此是二次锂电池非常有希望的正极材料.