质谱技术研究进展

质谱技术具有高灵敏度、高精确度等特点，已广泛应用于生物学、生物医学、生物化学等学科的研究，特别是在蛋白质等生物大分子的研究中作用越来越重要。对质谱技术的研究现状及新技术的研究进展作一综述，并对未来予以展望。     

蛋白质组学研究方法及其在生物医学中的应用

蛋白质组学方法发展迅速，并日见成熟。蛋白芯片技术、双向电泳—质谱技术、多维液相色谱—质谱技术等，已被广泛应用于寻找疾病相关的差异表达蛋白质、疾病相关的生物标记分子以及药物靶点用于临床诊断、药物设计、以及疾病发病机理的研究等。本文对上述研究进展作了简要综述。     

基于质谱技术的新兴蛋白质组学及其应用研究

随着分子生物学的深入研究以及蛋白质组学技术的发展,对蛋白质的研究已从简单的蛋白质化学发展到蛋白质组学阶段,质谱技术已成为蛋白质组学研究中的重要工具和核心技术。而基于质谱技术的蛋白质组学已开始成熟,这为生命活动规律的研究提供了手段,为临床应用的研究提供给了新的思路和方法。文章综述了近年来基于质谱的新兴蛋白质组学的研究及其最近的突出应用,并对其发展前景进行展望。     

生物质谱分析的研究进展及临床应用

质谱分析技术已应用于化学、化工、环境、能源、医药、运动医学、刑侦科学、生命科学、材料科学等各个领域.阐述目前生物质谱技术的类型、原理以及在医学领域中的应用,进而分析质谱技术在未来发展的前景.     

基于生物质谱的定量蛋白质组学分析策略

生物质谱技术作为蛋白质组学研究的关键技术 ,在定量蛋白质组学分析中起着十分重要的作用。目前基于生物质谱的定量蛋白质组学分析策略主要有 :荧光染色差异显示双向电泳、同位素代谢标记、同位素亲和标记 ,氨基酸化学标记和肽质图谱差异比较等     

质谱技术分析磷酸化蛋白的研究进展

蛋白质的可逆磷酸化是最重要的翻译后修饰之一,几乎参与生命活动的所有过程。虽然对于磷酸化蛋白的全面解析还存在巨大挑战,质谱已逐渐被人们认为是挑战这一领域的有利工具。质谱技术分析磷酸化蛋白质的方法包括利用抗体免疫沉淀、磷酸化蛋白胶染色、固定化的金属亲和层析柱、化学标签、强阳离子交换等技术富集磷酸化蛋白或肽段,串联质谱、电子俘获分析等技术检测磷酸化肽段并鉴定磷酸化位点,以及同位素标签对蛋白质磷酸化水平进行定量等。     

空间代谢组学在肿瘤中的应用及前景

空间代谢组学是基于质谱成像技术, 对组织中代谢物的种类、含量、空间分布差异进行分析, 具有无需标记、免基质、灵敏度高的特点, 相比传统代谢组学增加了对空间信息的研究。本文介绍代谢组学和质谱成像技术以及它们的研究现状, 重点综述空间代谢组学在肿瘤各个领域的应用, 介绍了空间代谢组学技术的现有瓶颈并展望了其未来发展方向。     

蛋白质组中蛋白质鉴定技术的研究近况

蛋白质组学的核心内容之一就是蛋白质的鉴定 ,基于双向凝胶电泳的图象分析技术可以对组织细胞蛋白质表达的量、表观分子量和等电点等特性进行初步的鉴定 ,但是对于蛋白质的结构和功能必须借助其它技术手段。目前逐渐形成了以生物质谱为核心的鉴定技术 ,蛋白质微测序和氨基酸组成分析在表达模式分析中也有应用。关于蛋白质组功能模式研究目前可用的方法有酵母双杂交、噬菌体展示、生物传感芯片质谱、蛋白质工程中的定点突变技术等。这些技术对推动蛋白质组学的发展起了一定作用 ,但是单一技术通常不能确切的鉴定某一蛋白质 ,常需联合应用几种技术才能准确的鉴定蛋白质     

构建新生儿遗传代谢病筛查诊断体系促进精准防控

遗传代谢病是一类表现为代谢异常的出生缺陷.生化检查是检测代谢异常的传统手段,其中串联质谱技术可高效实现一种实验检测多种疾病,对新生儿筛查具有重要意义.由于筛查的仪器、试剂和分析软件大量依赖进口,筛查成本高,加之不同地区操作水平和技术规范存在差异,我国新生儿串联质谱筛查存在检测质量不均一、人工初筛假阳性率高、筛诊治脱节等问题.针对这些问题,"生殖健康及重大出生缺陷防控研究"十三五国家重点研发计划项目"新生儿遗传代谢病筛查诊断集成化产品自主研发"集合产业创新技术力量,从串联质谱设备和配套试剂开发入手,建立了从前处理、质谱分析到数据人工智能化诊断的国产化新筛产品体系.初筛阳性率降低至0.5％以下,减轻了召回负担,提升了诊断准确性.在遗传诊断产品研发上,基于微流控芯片技术、核酸质谱技术和高通量测序技术,分别形成可覆盖中低、中高、高通量等不同通量需求的基因诊断产品,为遗传代谢病明确诊断提供有利手段.立足于筛诊实践经验和研究成果,项目组技术和临床专家形成了关于串联质谱筛查技术操作规范和多种遗传代谢病诊疗的专家共识.从而从技术、产品、标准和推广应用上全方位构建起一套为新生儿遗传代谢病精准防控服务的筛查诊断体系.     

现代色谱光谱分析技术在金银花研究中的应用进展

金银花的现代研究涉及到色谱、光谱、质谱及指纹图谱等多种分析方法。我们就近5年国内外现代分析技术在金银花中的应用研究做一综述。     

Structural characterziation of pollen allergens

The molecular characterization of allergens has accelerated significantly since the wide-spread implementation of modern analytical methods. The combination of gene cloning and heterologous protein expression has generated an extensive array of allergens that is available for comparative analysis, as well as clinical applications. Several internet-accessible allergen databases integrate the accumulated information from biomedical research and clinical practice. Innovations in classical biophysical methods, such as mass spectrometry, X-ray crystallography, and nuclear magnetic resonance spectroscopy, have rendered complex biological macromolecules amenable to detailed structured analysis. The modern scientific era has realized the synthesis of bioinformatics, molecular biology, biochemistry, biophysics, and immunology, and given us the means needed to decipher the remaining mysteries of allergies. This article addresses how the synergism of modern scientific techniques has hastened our understanding of allergies, how these techniques are applied in the identification and characterization of allergens, and how these methods assist the radional development of clinical tools for allergy diagnosis and treatment.     

Surface-MALDI mass spectrometry in biomaterials research

Matrix-assisted laser desorption ionization mass spectrometry (MALDI-MS) has been used for over a decade for the determination of purity and accurate molecular masses of macromolecular analytes, such as proteins, in solution. In the last few years the technique has been adapted to become a new surface analysis method with unique capabilities that complement established biomaterial surface analysis methods such as XPS and ToF-SSIMS. These new MALDI variant methods, which we shall collectively summarize as Surface-MALDI-MS, are capable of desorbing adsorbed macromolecules from biomaterial surfaces and detecting their molecular ions with high mass resolution and at levels much below monolayer coverage. Thus, Surface-MALDI-MS offers unique means of addressing biomaterial surface analysis needs, such as identification of the proteins and lipids that adsorb from multicomponent biological solutions in vitro and in vivo, the study of interactions between biomaterial surfaces and biomolecules, and identification of surface-enriched additives and contaminants. Surface-MALDI-MS is rapid, experimentally convenient, overcomes limitations in mass resolution and sensitivity of established biochemical techniques such as SDS-PAGE, and can in some circumstances be used for the quantitative analysis of adsorbed protein amounts. At this early stage of development, however, limitations exist: in some cases proteins are not detectable, which appears to be related to tight surface binding. This review summarizes ways in which Surface-MALDI-MS methods have been applied to the study of a range of issues in biomaterials surfaces research.     

Matrix‐assisted laser desorption ionization time‐of‐flight mass spectroscopy of polydimethylsiloxanes prepared via anionic ring‐opening polymerization

Poly(dimethylsiloxane) prepared by the anionic ring‐opening polymerization initiated by butyllithium in tetrahydrofuran has been examined by MALDI TOF mass spectrometry. The molecular weight distributions have been found to be different from those obtained by SEC, with the MALDI spectra underestimating the contribution of the higher mass macromolecules leading to an underestimation of the average molecular weights. Three distributions are observed in the mass spectra that correspond to the initiation and interchain‐exchange mechanisms producing three different macromolecular species. The pre‐dominant species is an integral sum of the repeat unit indicating that anionic ring‐opening propagation is fast when compared to intermolecular chain transfer. This is in conflict with earlier studies and indicates that the relative rates of transfer by different processes are highly dependent upon reaction conditions.     

Synthesis of Comb‐Like Macromolecules via Semi‐Batch Miniemulsion RAFT Polymerizations

Construction of macromolecule topology and control of chain sequence are foundations to endow macromolecules with complex functionalities. Comb‐like macromolecules have more designable freedom because their backbones and branched chains can be independently designed and synthesized. Herein, the rigid backbones of comb‐like macromolecules are synthesized by ring‐opening metathesis polymerizations of norbornene derivatives anchoring reversible addition–fragmentation chain transfer (RAFT) agent. The gradient branched chains with controlled sequence structure are synthesized through a modified RAFT miniemulsion polymerization of 4‐vinylpyridine and t‐butyl acrylate in a semi‐batch manner. These comb‐like macromolecules self‐assemble into aggregates when a dilute solution of comb‐like macromolecules are brushed onto a silicon wafer. The self‐assembly behavior of comb‐like macromolecules is affected by grafting ratio and sequence structure of branched chains. The effect of these comb‐like macromolecules on water contact angle of silicon wafer is also studied.     

Kinetics and mechanism of formation and properties of polymers composed of paired macromolecules

The influence of formation conditions on structure and properties of reaction products from two different macromolecules (paired polymers) such as polystyrene and poly(1,1,2-trichlorobutadiene) or polystyrene and poly(vinyl chloride) is investigated. Mechanical properties, molecular mobility, heat resistance, thermostability, and fire resistance are shown to be regulated over a wide range by changing the molecular weight of the initial polymers, their ratio in the reaction mixture, etc. The interaction of different macromolecules in solution to form paired polymers is analyzed theoretically and experimentally. An analysis of structure and properties of the resulting products by refractometry, viscometry, sedimentation velocity, statistical analysis, and others shows that paired polymers are systems of the “coil-in-coil” type held together by chemical bonds in the zones of mutual penetration.     

Staphylococcal slime: a cautionary tale.

Slime production by Staphylococcus epidermidis may be important in the adherence to and colonization of biomedical devices, and slime has been proposed to have various effects on the immune system. Attempts were made to isolate, purify, and chemically characterize slime from S. epidermidis cultivated under fluid on tryptic soy broth-agar medium. "Crude slime" from slime-producing strain RP-12 was characterized by a high galactose content. Similar materials in similar yields were isolated from slime-producing strain Kaplan, a non-slime-producing mutant, Kaplan-6A, and sterile medium controls, suggesting that crude slime was derived mainly from the medium. The occurrence of D- and L-galactose and pyruvate and sulfate residues and methylation analysis of these crude slime preparations, monitored by gas-liquid chromatography and mass spectrometry, showed that the agar was the main source of crude slime, suggesting that the preparation was largely an artifact of the growth and isolation procedures. Similar high-galactose-content preparations from both S. epidermidis and Staphylococcus aureus, assumed to be bacterial products and with a variety of biological activities, have been described by other investigators. Growth attached to a solid surface appears to be important for slime production. An accumulation of turned-over cell surface molecules and released macromolecules such as DNA may contribute to slime production. Avoidance of agar and development of a chemically defined medium for slime production are recommended for further studies.     

Hyphenated liquid chromatographic techniques in forensic toxicology

The prerequisite of applicability of hyphenated methods in forensic analysis is the achievement of a stage of "final maturity". In the field of liquid chromatography, HPLC coupled with diode array detection (DAD) seems to fulfill this criterion, whilst the combination with atmospheric pressure ionization mass spectrometry (HPLC-API-MS) is still in a development stage. HPLC-DAD is broadly used as identification tool in forensic and in emergency toxicology. Two main approaches were observed; development of retention index scales for intra-laboratory exchange of data and establishing of databases only for intra-laboratory use. Using these approaches, several databases were established for toxicological relevant substances (illicit and therapeutic drugs and their metabolites, environmental poisons etc.) in biological fluids. Also, complete HPLC-DAD identification systems are commercially available. Further possibility of progress depends on the on-line combination ("triple hyphenation") with other detection methods, preferably API-MS. HPLC-API-MS, both in electrospray (ESI) and atmospheric pressure chemical ionization (APCI) options, underwent dramatic development in the last decade and is reaching its final shape. The method was broadly applied for various groups of toxicologically relevant substances, a lot of them unaccessible for other techniques, including GC-MS. Particularly important was application of HPLC-API-MS for detection and quantitation of active, polar metabolites of various drugs and for analysis of macromolecules. APCI seems to be more useful for analysis of less polar compounds, whereas ESI is particularly valuable for determination of polar, large molecules (e.g., toxic peptides, polar metabolites etc.) Up to now, HPLC-API-MS has been mainly applied for dedicated analyses, but the introduction of APCI or ESI in systematic toxicological screening may be expected in the near future.     

Modern physical methods for analysing elements and structures in histochemistry

Chemical analysis supported to a greater and greater degree by physical principles and measurement techniques offers some advantages for application in biomedical research and is able to complete histochemical procedures in elemental analysis. The described methods, such as electron-probe X-ray microanalysis, Auger electron spectrometry, cathodoluminescence analysis, electron diffraction, secondary ion mass spectrometry, electron spectrometry for chemical analysis, laser microprobes based on emission spectrometry, mass spectrometry and luminescence spectrometry yield qualitative and quantitative information about the inorganic (and organic) constituents and their distributions of subcellular microvolumes of biological tissues. Information content, figure of merit, applications, and limitations of these methods, and the special preparation techniques of biological materials are discussed.