A chip-based miniaturized format for protein-expression profiling: the exploitation of comprehensively produced antibodies

Numerous antibodies have been developed and validated in recent years, and show promise for use in novel functional protein assays. Such assays would be an alternative to pre-existing comprehensive assays, such as DNA microarrays. Antibody microarrays are thought to represent those functional protein assays. While a variety of attempts have been made to apply DNA microarray technology to antibody microarrays, a fully optimized protocol has not been established. We have been conducting a project to comprehensively produce antibodies against mouse KIAA ("KI" stands for "Kazusa DNA Research Institute" and "AA" are reference characters) proteins. Using our library of antibodies, we established a novel antibody microarray format that utilizes surface plasmon resonance (SPR) technology. A label-free real-time measurement of protein expression in crude cell lysates was achieved by direct readout of the bindings using SPR. Further refinement of the antibody microarray format enabled us to detect a smaller quantity of target proteins in the lysate without the bulk effect. In this review, we first summarize available antibody array formats and then describe the above-mentioned format utilizing updated SPR technology.     

舌尖上的化学——酱油那些事儿

As an old saying goes: "firewood, rice, oil, salt, sauce, vinegar, tea", as one of the most popular seasonings in the kitchen, soy sauce brings us rich taste experience every day. In order to give readers a more comprehensive and in-depth understanding of this condiment that is closely related to our lives, this paper introduces the history of soy sauce, brewing technology and the formation principle of color and flavor from the perspective of chemistry.     

Evolution of polyhydroxyalkanoate (PHA) production system by "enzyme evolution": successful case studies of directed evolution

Biotechnological studies towards the biosynthesis of polyhydroxyalkanoates (PHAs) biopolyesters have extensively progressed through the development of various metabolic engineering strategies. Historically, efficient PHA production has been achieved using the fermentation technology of naturally occurring PHA-producing bacteria based on external substrate manipulation (1st generation), and subsequent reinforcement with recombinant gene technology (2nd generation). More recently, "enzyme evolution" is becoming the 3rd generation approach for PHA production. A break-through in the chemical synthesis of macromolecules with desirable properties was achieved by the development of prominent chemical catalysts via "catalyst evolution", as represented by a series of Ziegler-Natta catalysts. Thus, one can easily accept the concept that the molecular evolution of the biocatalysts (enzymes) relevant to PHA synthesis will provide us with a chance to create novel PHA materials with high performance. The first trial of an in vitro enzyme evolution in PHA biosynthesis was reported by our group in 2001. The following literature data, as well as our own experimental results devoted to this new approach, have been accumulated over a short time. This review article focuses specifically on the concept and current case studies of the application of "enzyme evolution" to PHA biosynthesis.     

Automated process for improved uniformity and versatility of layer-by-layer deposition

The recently developed practice of spraying polyelectrolyte solutions onto a substrate in order to construct thin films via the layer-by-layer technique has been further investigated and extended. Here we describe a fully automated system capable of depositing thin polymer films from atomized mists of solutions containing species of complementary functionality. Film growth is shown to be similar to that in conventional "dipped" LbL assembly, whereas the reported technology allows us to realize 25-fold decreases in process times. Furthermore, complete automation removes human interaction and the possibility of operator-induced nonuniformities. We extend the versatility of the spray LbL technology by depositing both weak and strong polyelectrolyte films, hydrogen-bonded films, and dendritic compounds and nanoparticles, broadening its range of future applications. Finally, the technology is used to uniformly coat an otherwise hydrophobic substrate from aqueous solutions. ESEM images indicate that the atomization process produces a conformal coating of individual nanofibers within the substrate, dramatically changing the hydrophilicity of the macroscopic surface. Such an automated system is easily converted to an array of nozzle banks and could find application in the rapid, uniform coating of large areas of textile materials.     

Femtosecond lasers in gas phase chemistry

This critical review is intended to provide an overview of the state-of-the-art in femtosecond laser technology and recent applications in ultrafast gas phase chemical dynamics. Although "femtochemistry" is not a new subject, there have been some tremendous advances in experimental techniques during the last few years. Time-resolved photoelectron spectroscopy and ultrafast electron diffraction have enabled us to observe molecular dynamics through a wider window. Attosecond laser sources, which have so far only been exploited in atomic physics, have the potential to probe chemical dynamics on an even faster timescale and observe the motions of electrons. Huge progress in pulse shaping and pulse characterisation methodology is paving the way for exciting new advances in the field of coherent control.     

Entropy-driven complex formation of malvidin-3-O-glucoside with common polyphenols in ethanol-water binary solutions

The complex formation of malvidin-3-O-glucoside with several polyphenols, the so-called "copigmentation" phenomenon, was studied in aqueous solutions. To simulate the copigmentation process during fermentation, the stability of the formed complexes was examined in dependence of the ethanol content of the aqueous solution. Results indicate that stronger and larger complexes are formed, when the ethanol content exceeds a critical margin of 8vol.% However, the size of complexes of malvidin/procyanidin and malvidin/epicatechin is drastically reduced above this critical concentration. Fluorescence lifetime and solvent relaxation measurements give insight into the particular processes at molecular level and will help us comprehend the first important steps during winemaking in order to recommend an optimized winemaking technology to ensure extraordinary colour stability in red wines.     

The Use of a Thin Glass-Ceramic Rod as a Surface for Sol-Gel Coating in the Preparation of SPME Fibers

The efficiency of a glass-ceramic rod as a base for the preparation of SPME fibers using sol-gel technology was investigated. Glass-ceramic rod was coated with PDMS using sol-gel reaction, and its surface characteristic was determined for SEM. Optimum conditions for the preparation of the fiber are presented. The same procedure was used for coating the fused silica rod. The fibers thickness and absorption capacity were compared. The proposed fiber was used for the extraction of a mixture of BTEX, from aqueous samples. The results obtained proved the superiority of glass-ceramic as a new base for SPME fiber, resulting in a thickness of ~44 m against 6 m for fused silica base. The calibration graphs for BTEX were linear (r > 0.998) and the detection limits were below 0.8 g L^–1.     

逆流色谱技术分离蛋白质和多肽的研究进展

逆流色谱是一种连续高效的液-液分配色谱技术,具有进样量大、无不可逆吸附、回收率高和能有效保护样品生物活性等优点,在蛋白质和多肽的分离中具有独特的优势。本文综述了近年来几种新型的逆流色谱技术在蛋白质和多肽分离中的研究进展,并对该领域的未来发展进行了展望。     

Analytical chemistry—seen in perspective

The many faceted perspectives which can be constructed with analytical chemistry as baseline, information as horizon and truth as vanishing point illustrate the diversity of our scientific work.We will only make a major step forward after we have learned to understand the perspectives of the role of the sample as the representative of the collective which we want to investigate, as the central object of pragmatic analysis, and as the Janus-headed synholon of matter and information.This still somewhat unusual alter-ego point of view forces us to quantify intensive and qualify extensive parameters, e. g. in the field of pattern recognition. This view, together with a radical change away from the adaption of the sample to the method (instead of the more logical way of adaption), and the right selection of the reagent matched to the sample, will in the future change the image of analytical chemistry to that of scientific analysis.This is an attempt to illustrate the enormous importance of analytical chemistry as scientific analysis and in the perspective of the gain of information, without including the increasing importance of analytical chemistry in society, economy and technology.Dedicated to you, dear Karl (Winsauer), on the occasion of your 60th birthday in recognition of your pioneering contribution to the consolidation of analytical chemistry.     

Fast isolation of hydrophobic organic environmental contaminants from exposed semipermeable membrane devices (SPMDs) prior to GC analysis

Semipermeable membrane devices (SPMD) represent a passive sampling technology that is becoming widely used for monitoring of surface waters pollution. While "classic" procedures employ dialysis to recover target compounds from exposed SPMDs, in the present study analytes were isolated from cut membrane together with sequestering medium (triolein) using hexane as an extraction solvent. This approach allowed us to reduce the time needed for accomplishment of isolation step from 48 h to only 1 h. Automated gel permeation chromatography (GPC) clean-up is employed in the following step to separate triolein from analytes fraction. Musk compounds (MCs), polychlorinated biphenyls (PCBs), brominated flame retardants (BFRs) and several other persistent organochlorine compounds (OCs) were determined in the respective fraction by GC method employing selective detectors (MSD, ECD). As shown in a series of analyses of SPMDs deployed in various aquatic ecosystems, high recoveries and good repeatability of results together with a possibility to obtain the information on the pollution of sampling site at the day of sample arrival to laboratory make this newly implemented procedure an interesting alternative to time consuming dialysis.     

Slide-format proteomic biochips based on surface-enhanced nanocluster-resonance

The most fundamental properties of metal nanoclusters, namely the high local-field enhancement and nanoscale resonance behavior of the cluster electron plasma when exited by electromagnetic radiation, have been used to set up a variety of sensors transducing biorecognitive interactions into optical signals. This paper focuses on applications of resonant-cluster technology, which enabled us to monitor biorecognitive binding of a variety of proteins on a chip, thus constructing high-throughput interaction-screening devices. Decisive for this type of sensor is the nanometric distance from the local field surrounding a cluster to other parts of the sensor interacting with this field. In particular, the cluster-mirror or cluster-fluorophore distance gives rise to a variety of enhancement phenomena. Depending on the desired application this "resonance"- distance is approximately 5-400 nm. All types of sensor can be set up on photolithographically constructed microchips, but microscopic glass slides can also be employed; this also enables the use of standard devices for dotting and read out. Using slide based chips a standard format of 3,200 microdots (125 microm in diameter) was the basis of either microassays applying direct optical transduction via surfaceenhanced absorption or striking for more sensitivity via surface-enhanced fluorescence.     

PEGylated Click Polypeptides Synthesized by Copper‐Free Microwave‐Assisted Thermal Click Polymerization for Selective Endotoxin Removal from Protein Solutions

PEGylated click polypeptides ( PEG‐CP s) containing α‐amino side groups as well as PEG segments are designed for selective endotoxin removal from protein solutions. The PEG‐CP s are synthesized via copper‐free thermal click copolymerization from aspartic (or glutamic) acid‐based dialkyne and diazide monomers (containing free amino side groups) and alkyne‐terminated mPEGs or dialkyne‐terminated PEGs. Microwave‐assisting technology is introduced into thermal click chemistry to improve the reaction efficiency. The monomers and polymers are fully characterized using NMR, XPS, and MALDI‐TOF MS. After immobilizing the PEGylated click polypeptides onto polystyrene microspheres, the adsorbents exhibit good endotoxin removal selectivity from BSA solutions.

     

Microwave‐activated Synthesis of Pyrroles: A Short Review

In the current scenario for continuous requirement of better drugs, medicinal chemists must visage the challenging task of preparing novel patentable compounds, combining high activity and selectivity, good drug‐likeness, and pharmacokinetic properties. There is an acute need of new molecules in both lead identification and lead optimization. Chemists thoroughly scrutinize ways to simplify synthetic protocols using green chemistry approaches, for example, microwaves. Reduction in the reaction time by the use of microwaves has emerged as a promising method for bringing out new leads in organic synthesis. Among the azaheterocyclic systems, synthesis of pyrrole moiety has been a highly attractive and an inspiring proposition. It has been found to be an inbuilt pharmacophore of various momentous pharmacologically active compounds in medicinal chemistry. This article outlines the basic principles of microwave technology and its use in the synthesis of pyrrole derivatives wherein this technology has made a tremendous impact.     

The relationship between electronic charges and lengths of σ-bonds

Summary A dependence was shown to exist between the electronic charges and the lengths of -bonds of a saturated carbon atom, which permitted us to explain and to correct the existing data on interatomic distances.     

基于化学的“化学测量学与技术”新工科专业建设建议

The background of the establishment of "chemistry metrology and technology" as an emerging engineering education major based on chemistry is analyzed. Based on the national development strategy, aiming at the urgent demand of interdisciplinary talents for the rapid development of chemistry metrology and technology, the necessity of setting up the major of "chemistry metrology and technology" based on chemistry is demonstrated. Based on the investigation of professional talents in instrument development enterprises and application fields, some suggestions on the program of "chemistry metrology and technology" major including orientation, objectives, graduation requirements and professional training are provided. Some requirements of the curriculum, teaching staff and teaching conditions are put forward.     

Recent advances in surface plasmon resonance based techniques for bioanalysis

Surface plasmon resonance (SPR) is a powerful and versatile spectroscopic method for biomolecular interaction analysis (BIA) and has been well reviewed in previous years. This updated 2006 review of SPR, SPR spectroscopy, and SPR imaging explores cutting-edge technology with a focus on material, method, and instrument development. A number of recent SPR developments and interesting applications for bioanalysis are provided. Three focus topics are discussed in more detail to exemplify recent progress. They include surface plasmon fluorescence spectroscopy, nanoscale glassification of SPR substrates, and enzymatic amplification in SPR imaging. Through these examples it is clear to us that the development of SPR-based methods continues to grow, while the applications continue to diversify. Major trends appear to be present in the development of combined techniques, use of new materials, and development of new methodologies. Together, these works constitute a major thrust that could eventually make SPR a common tool for surface interaction analysis and biosensing. The future outlook for SPR and SPR-associated BIA studies, in our opinion, is very bright. Surface plasmon resonance (SPR) is a powerful and versatile spectroscopic method for biomolecular interaction analysis (BIA) and has been well reviewed in previous years. This updated 2006 review of SPR, SPR spectroscopy, and SPR imaging explores cutting-edge technology with a focus on material, method, and instrument development. A number of recent SPR developments and interesting applications for bioanalysis are provided. Three focus topics are discussed in more detail to exemplify recent progress. They include surface plasmon fluorescence spectroscopy, nanoscale glassification of SPR substrates, and enzymatic amplification in SPR imaging. Through these examples it is clear to us that the development of SPR-based methods continues to grow, while the applications continue to diversify. Major trends appear to be present in the development of combined techniques, use of new materials, and development of new methodologies. Together, these works constitute a major thrust that could eventually make SPR a common tool for surface interaction analysis and biosensing. The future outlook for SPR and SPR-associated BIA studies, in our opinion, is very bright.      

Staying Alive: Measuring Intact Viable Microbes with Electrospray Ionization Mass Spectrometry

Mass spectrometry has traditionally been the technology of choice for small molecule analysis, making significant inroads into metabolism, clinical diagnostics, and pharmacodynamics since the 1960s. In the mid-1980s, with the discovery of electrospray ionization (ESI) for biomolecule analysis, a new door opened for applications beyond small molecules. Initially, proteins were widely examined, followed by oligonucleotides and other nonvolatile molecules. Then in 1991, three intriguing studies reported using mass spectrometry to examine noncovalent protein complexes, results that have been expanded on for the last 25 years. Those experiments also raised the questions: How soft is ESI, and can it be used to examine even more complex interactions? Our lab addressed these questions with the analyses of viruses, which were initially tested for viability following electrospray ionization and their passage through a quadrupole mass analyzer by placing them on an active medium that would allow them to propagate. This observation has been replicated on multiple different systems, including experiments on an even bigger microbe, a spore. The question of analysis was also addressed in the early 2000s with charge detection mass spectrometry. This unique technology could simultaneously measure mass-to-charge and charge, allowing for the direct determination of the mass of a virus. More recent experiments on spores and enveloped viruses have given us insight into the range of mass spectrometry’s capabilities (reaching 100 trillion Da), beginning to answer fundamental questions regarding the complexity of these organisms beyond proteins and genes, and how small molecules are integral to these supramolecular living structures.

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Laboratory robotics — Past,present, and future

In the past four years, laboratory robotics has emerged as an important subset of automation technology. It offers chemists an approach to tackling the difficult problems that arise when attempting to automate sample preparation procedures. Successful implementations of this technology yield cost and labor savings, improved assay precision, increased data output, improved morale, and improved worker safety. This paper introduces the principles of this growing technology, summarizes the current state of the art, and suggests some of its future possibilities. The principles of laboratory robotics are discussed in the context of a system developed from an in-house technology base. This system has been performing pH and fluoride determinations for the past two years. The current state of laboratory robotics technology is examined by presenting our experiences with an all-commercial immunoassay system from Zymark. The future of this technology is very promising. Recent innovations by a variety of vendors promise to make the technology easier to use. In the next decade, the combination of more powerful microcomputers and software should produce systems that can learn and optimize their own performance.     

中山大学化学"拔尖计划"人才培养探索

介绍了中山大学化学学院"基础学科拔尖学生培养试验计划"项目的开展情况,从培养目标、实施探索和实施成效三个方面对近年来中山大学化学学院拔尖学生人才培养模式进行了系统全面的总结,为今后"拔尖计划"的实施和改进提供了有益的借鉴。