Research and development activities on radioimmunoassay at CIAE

Research and development activities on the field of radioimmunoassay has been reviewed in the past decade at China Institute of Atomic Energy (CIAE), including polyclonal and monoclonal antibodies, recombinant antigens, radioiodination method and tracer purification, separation systems, and nonisotopic label immunoassay.     

Recent advances in the development of Fischer-Tropsch catalysts at sasol

Sasol's experience of more than 50 years in the field of Fischer-Tropsch puts it in a unique position to exploit the renewed interest in the utilization of the Fischer-Tropsch process to convert natural gas to liquids. In order to capitalize on this position, Sasol has made significant improvements to its low temperature and high temperature Fischer-Tropsch catalysts. A review is given of the development of Sasol's Co-based catalyst for low temperature Fischer-Tropsch applications. Sasol has also developed a new Fe-based catalyst for the high temperature Fischer-Tropsch process. The advantages of this catalyst compared to the existing catalyst are discussed.     

Recent developments in zinc oxide target chemistry

Zinc oxide targets irradiated with high energy protons at the Los Alamos Meson Physics Facility (LAMPF) contain a number of radioactive spallation products in quantities large enough to warrant recovery. This paper describes methods for recovering⁷Be,⁴⁶Sc, and⁴⁸V from such targets and offers suggestions on possible ways to recover additional isotopes. The proposed methods are based on traditional precipitation and ion exchange techniques, are readily adaptable to hot cell use, and produce no hazardous waste components. The products are obtained in moderate to high yields and have excellent radionuclidic purity.     

色谱研究的最新重要进展

细内径毛细管柱自由溶液用于分离宽范围DNA片段 凝胶电泳是分离DNA最高效的方法,但将凝胶注入微纳分离通道或细内径毛细管柱内存在很大的技术难度。为了克服这一技术难题,美国University of Oklahoma的Shaorong Liu和University of Texas at Arlington的P. K. Dasgupta等在无胶、无管壁改性和无外加电场的情况下,应用流体动力学原理在细内径毛细管柱上实现了宽范围 (75 bp ～106 kb)DNA片段的高效分离。他们还对分离后所采集的DNA片段的馏分进行了聚合酶链反应(PCR)扩增实验,发现采集的DNA片段保持了良好的扩增活性。(来源: J. Am. Chem. Soc., 2010, 132: 41－41) LC-MS/MS技术分离鉴定饮用水中的2,6-二氯-1,4-苯并醌 用化学试剂对饮用水进行杀毒处理是水处理中广泛采用的技术和方法,对于饮用水中致病菌的灭杀和防止流行病的发生具有重要作用。饮用水杀毒处理过程中的化学试剂有可能与水中的其他有机试剂发生反应,产生对人体具有毒副作用的副产物。加拿大University of Alberta的Feng Qin和Xingfang Li等发展了固相萃取样品预处理和LC-MS/MS的多级反应监测(MRM)的分离分析集成技术,对水中卤代醌的检测灵敏度达到3～8.7 ng/L。他们采用所发展的方法在饮用水中检测到由于化学试剂杀毒处理产生的副产物2,6-二氯-1,4-苯并醌,这是国际上第一次在饮用水中检测到2,6-二氯-1,4-苯并醌的报道。(来源: Angew. Chem. Int. Ed., 2010, 49: 790－792) 反相-反相二维液相色谱高效分离分析磷酸化肽的新方法 磷酸化肽的高效分离分析对磷酸化蛋白质组学研究具有重要的意义。多维色谱是实现磷酸化肽高效分离分析的最有效的途径。中国科学院大连化学物理研究所的叶明亮和邹汉法等发展了高正交性反相-反相二维液相色谱分离磷酸化肽的新方法。他们通过对分离流动相的优化,首先将富集的磷酸化肽混合物在高pH流动相下进行90 min的梯度分离,并在每1 min采集一个馏分,再将每间隔45 min的馏分混合(如1 min与46 min馏分混合,2 min与47 min馏分混合……),总计产生45个馏分。第一维分离的常规方法是每2 min采集一个馏分(0－2 min馏分,2－4 min馏分……), 90 min的梯度分离可采集45个馏分。在低pH流动相下采用毛细管反相液相色谱-质谱联用技术对第一维采集的馏分进行分离鉴定,发现第一维分离中将每间隔45 min的馏分进行混合的方式可以有效提高二维分离的正交性;与常规的每2 min采集一个馏分的方式相比较,磷酸化肽的鉴定能力提高了30%以上。他们将发展的方法应用于肝脏磷酸化蛋白质组的规模化分析,在将假阳性率控制在1%以下(即FDR＜1%)的条件下初步鉴定了8000个以上的磷酸化位点。(来源: Anal. Chem., 2010, 82: 53－56) 纳流通道分离阿升(Attoliter)级样品的飞升(Femtoliter)级液相色谱至今尚无良好的方法与手段对珍贵的极微量生物样品进行分离分析。日本University of Tokyo的Takehiko Kitamori等报道了飞升级液相色谱(fLC)的研究成果。他们在玻璃微芯片上制备了宽度和深度为几百纳米的纳流通道。该系统的尺寸只有常规液相色谱系统的1/1011左右,流动相的流量为亚pL/min,进样量为几百阿升。fLC无需分离固定相,可以分离电荷不同的化合物。fLC可以克服常规液相色谱分离固定相非均一性和涡流扩散的缺点。液相色谱尺寸的缩小不仅具有进样量小的优点,而且可有效提高分离效率。fLC可以应用于极微量样品(如单细胞样品)的高效分离分析。(来源: Anal. Chem., 2010, 82: 543－547) 全二维气相色谱-飞行时间质谱应用于化学武器前体痕量杂质的特征指纹分析 化学攻击作为潜在的恐怖活动正日益引起关注。美国University of Washington的Carlos G. Fraga等探讨了将样品分析和化学计量学相结合的方法用于化学攻击犯罪案件中法医鉴定的可行性。他们以一种有可能作为化学武器攻击的有毒试剂——甲基磷酸二甲酯(DMMP)作为模型化合物,以29种痕量杂质为检测对象,应用全二维气相色谱-飞行时间质谱(GC×GC-TOF)对6批DMMP样品中的痕量杂质进行了指纹分析。进一步使用平行因子法(PARAFAC)对重叠峰进行数学分辨处理获得清晰的谱图,并通过与谱图库中标准谱图的比对成功地鉴定了检测到的化合物。通过对每一对样品的数据进行统计分析,结果表明其中5批DMMP样品中的痕量杂质化合物的含量有些很相近,有些存在一定的差异。而有2批DMMP样品中的痕量杂质则具有完全相同的指纹谱图。运用非负矩阵因子分析发现,DMMP样品由于得分值不同可以分为5类,其中有2个来自同一供应商的同一批样品不能实现区分,这是由于它们的痕量杂质含量相同造成的,而其他4个样品由于来自于不同批次或不同供应商而得到了很好的区分。这一结果表明可以通过痕量杂质的指纹分析有效追踪DMMP产品的来源。此外,他们还发现不同公司的某些DMMP样品存在特异性的痕量杂质分布。因此所发展的方法有可能成为化学攻击犯罪案件中法医鉴定可采用的有效手段。(来源: Anal. Chem., 2010, 82: 689－698)     

色谱研究最新进展

色谱作为一种强大的分离分析手段,为推动生物医学和人类健康、环境监测与保护、食品安全与质检等领域的发展提供着解决问题的关键技术。最近几年来,我国色谱学科经历了全面快速发展,取得了令人瞩目的成绩,研究水平和国际地位得到巨大提升,色谱相关SCI论文发表数量居世界第一位。色谱应用领域也在不断扩大,尤其在蛋白质组学、代谢组学等新兴领域,以及药物、环境、食品分析等传统领域发挥越来越重要的作用。本文对近年来色谱学科(重点是我国色谱学科)在色谱技术、色谱填料和色谱柱、样品前处理方法、应用领域等方面的进展情况进行介绍。共引用109篇参考文献。     

Recent development of non-faradaic potentiometry

Non-faradaic potentiometry has been plagued by a great many fundamental errors and a lack of conceptualization. Of greatest concern is the second Nernst equation hiatus. Potentiometry may be generally classified as faradaic and non-faradaic. The former deals with the redox reactions using the Nernst equation to explain the potential origin. The latter deals with the non-redox reactions using the Boltzmann and modified Boltzmann equations to explain the origin of electrode potential. Redox faradaic potentiometry has been well described in the textbooks. However, non-faradaic potentiometry has been almost completely neglected in the literature. Many well-known electrodes, such as the pH glass electrode, common reference electrodes, and ion selective electrodes (ISE) have been mistakenly interpreted as redox reactions or ion exchange reactions. New theories and experimental results show their mechanisms to be non-faradaic in nature. Furthermore, the reaction mechanisms for ISE have been confused in textbooks with redox reactions and the Nernst equation. The ISE potentials originating from adsorption of ions or charged particles based on surface charge density will be explained using the double and counterion triple layers concept. The new counterion triple layer concept may be applied to the potential development of sensors. The reason for a new concept, theory, or mechanism is to better explain the phenomena. Examples will be given of how our new concept explains the capacitor, counterion triple layer, surface adsorbed layers interactions, and the interface structure. We will also discuss the new sensor development based on the new adsorption concept. For the first time a new type of Ag/AgCl reference electrode for non-faradaic potentiometry will be presented, one without a liquid junction and with a Pt wire instead of a salt bridge. They will help open up a new horizon for electrochemical sensor research and may be used under unusual conditions, such as high temperature and high pressure, stirring, etc.     

具有生理活性甾体金属配合物的研究进展

按照金属离子与甾体配体之间的连接方式对甾体金属配合物进行分类。综述了近年来合成的甾体金属配合物及其抗肿瘤、抗菌等多种生理活性研究进展,并对此类化合物发展趋势、应用前景作出展望。     

High intensity target wheel at TASCA: target wheel control system and target monitoring

At GSI Darmstadt, the gas-filled recoil separator transactinide separator and chemistry apparatus (TASCA) is in operation for experiments with superheavy elements. It is optimized for hot-fusion reactions with actinide targets. The small cross sections of such reactions require the capability to accept highest beam intensities. The limited availability of some of the exotic actinide isotopes limits the size of target systems. To maintain target integrity during long experiments, automated target monitoring and control is necessary. Here, the TASCA target wheel system and the on-line target monitoring are described.     

近期微流控芯片疾病诊断技术的研究进展

微流控芯片具有液流可控、样品消耗量小、反应速度快、易于集成化等特点,在临床诊断和疾病筛查领域具有广阔的发展前景。本文针对近年来微流控芯片技术在疾病诊断方面的最新研究进展,从疾病标志物检测、细胞筛选和药物代谢研究及疾病诊断微流控芯片装置的发展现状等方面概述其在疾病诊断方面的应用和发展。     

Recent development in heterogeneous metallocene catalysts

The synthetic methods of heterogeneous metallocene catalysts reported so far in academic journals are summarized together with their catalyst performance. Some of our new results in this field are also described in brief.     

抗体酶催化化学反应的新进展

本文评述了近几年来抗体酶催化化学反应的研究进展, 包括酯和酰胺的水解反应、脱羧反应、Claisen重排、Diels-Alder反应、不对称诱导作用、β-消去反应、金属络合物作用、氧化-还原反应、光诱导聚合和消除反应等, 讨论了介质效应和反应机理。     

Neutron induced reactions at the Athens Tandem Accelerator NCSR “Demokritos”

The neutron facility at the 5.5 MV tandem T11/25 Accelerator of NCSR “Demokritos” can deliver monoenergetic neutron beams in the energy range from thermal to 450 keV, 4–11.5 MeV and 16–20.5 MeV via the ⁷Li(p,n), ²H(d,n) and ³H(d,n) reactions, respectively. The flux variation of the neutron beam is monitored by using a BF₃ counter and a liquid scintillator BC501A detector. The ²³²Th(n,2n)²³¹Th and ²⁴¹Am(n,2n)²⁴⁰Am as well as (n,2n), (n,p) and (n,α) reactions on natural Ge and Hf isotopes, have been investigated from threshold up to 11.5 MeV, by using the activation method. The cross section values have been determined relative to the ¹⁹⁷Au(n,2n)¹⁹⁶Au, ²⁷Al(n,α)²⁴Na and ⁹³Nb(n,2n) reference reaction cross sections.     

β—氨基酸不对称合成研究的新进展

β-氨基酸是一类在医药开发和生物化学研究中有重要用途的化合物，立体选 择性地合成光学纯β-氨基酸具有挑战性．近10多年来人们在该领域开展了许多工 作．以最近几年的工作为主重点介绍了该领域具有代表性的工作。     

Recent trends in mass spectrometer development

Trends in mass analyzer development are reviewed here with an emphasis on tandem mass spectrometers. The move toward hybridization of conventional mass analyzers to allow additional instrument functionality in tandem mass spectrometry is discussed.     

Recent development in peptide coupling reagents

Two decades of domination of benzotriazole-based chemistry stimulated the progress in peptide synthesis to a high level of effectiveness. However, the growing need for new and more complex peptide structures, particularly for biomedical studies and, very recently, for the large-scale production of peptides as drugs, required manufacturing peptide products by efficient synthetic strategies, at reasonably low prices. Therefore, the search for new, more versatile and low-cost reagents becomes a great challenge. Several comprehensive review articles summarized the great effort undertaken, but up to now, no versatile coupling reagent useful for both amide and ester bond formation, as well as for solution and solid-phase peptide synthesis has been yet developed. The most-widely used coupling reagents are carbodiimides on one hand and phosphonium and aminium salts on the other. Herein in this review article, we summarized the recent development in peptide coupling reagents during the last two decades.     

Recent development on bio-based thermosetting resins

Due to the rapid depletion of crude oil and serious environmental pollution, the synthesis of polymers from renewable resource is becoming more and more important. Up to now, a great variety of biomass and bio-based platform compounds have been taken to prepare the polymers. However, as two representative thermosetting resins, epoxy and benzoxazine resin derived from renewable feedstocks only obtain limited attention compared with the popular bio-based plastics, including PLA, PBAT and PHBV etc. The reason might be that the properties of previously reported thermosetting resins directly obtained from biomass are usually unsatisfied, and their application fields are limited. In this paper, the latest development on the synthesis of high-performance bio-based epoxy and polybenzoxazine resins are reviewed. In addition, to further broaden their applications, the functionalization strategies are also summarized. The objective of this work is to help us fully aware the present situation of bio-based thermosetting resins and then promote their faster development, especially practical application.     

Recent instrumental neutron activation analysis studies utilizing very short-lived activities

The advantages and disadvantages of utilizing very short-lived induced activities (half lives in the range of 0.3 sec to 60 sec) in neutron activation analysis are reviewed. Results obtained with the recently described fast-transfer system and deadtime correction system are presented. They include results for 12 elements (F, S, Cl, Sc, Ge, Se, Br, Y, Zr, Ba, W, Pb), in both steady-state and high-intensity pulse irradiations, in both unlined and cadmium-lined irradiation positions. The half lives of the 12 species studied range from 0.3 sec to 18.7 sec. Some further aspects of the deadtime correction system are discussed.     

Recent advances in target identification by natural product based chemical probes

Natural products have been extensively used to treat diseases throughout human history. These are mainly because natural products normally target biological macromolecules selectively. Target identification could help us to develop new therapeutic agents and discover new biological pathways underlying human diseases. Herein, we highlight some recent examples of using natural products and their derivatives as chemical probes to identify the molecular targets and elucidate mode of action.     

Recent development in photosensitive resin in Korea

The aim of the review is to introduce some recent progress in the photosensitive polymers in Korea. It is focused to review the research works performed recently in this country, especially in the academic world. As photosensitive polymers, cinnamates of various polymers, azides and diazido compounds, oximeesters or oxime containing polymers, and some other sensitizing polymers were treated, and also sensitizing effects were evaluated.