液相色谱-质谱联用仪在实验教学研究中的应用

液相色谱-质谱联用仪在实验教学研究中发挥着日益重要的作用。本文阐述了液相色谱-质谱联用仪在环境检测(水体有机污染物、土壤有机污染物检测)、食品安全检测(农兽药残留、食品添加剂、食品营养物质与成分检测)、临床检验、药物分析等实验教学研究中的应用,加深学生对液相色谱-质谱联用仪的认识和理解,为利用液相色谱-质谱联用仪进行科学研究打下基础。     

液相色谱法测定苯甲酸山梨酸含量的研究

国家标准中液相色谱法样品处理方法适用于饮料中苯甲酸和山梨酸的检测,检测食醋、酱油中的苯甲酸和山梨酸时存在干扰严重、色谱柱污染的问题。通过样品的预处理实现一般液体食品中苯甲酸等防腐剂含量的测定。     

高效液相色谱技术的应用

高效液相色谱技术具有高选择性,可快速、准确地实现多种元素同时测定,方法简便快速。本文概述了高效液相色谱在应用方面的研究进展,同时还展望了高效液相色谱技术的应用前景。     

高效液相色谱系统的使用与维护

高效液相色谱法(HPLC)是现代分离分析的重要方法,广泛应用于食品、药品检查和含量测定等方面,高选择、高灵敏性为其主要特点。而整个高效液相色谱系统(包括管路,在线真空脱气机,输液泵,进样系统,色谱柱,检测器)的使用及维护至关重要。     

液相色谱在药物残留中的应用研究

药物在食品中的残留成为食品安全的重要的监测部分,本文通过分析液相色谱技术技术在药物残留检测方面的应用,并展望了液相色谱技术在药物残留应用方面的发展趋势。     

分析检测中液相色谱柱的选择及使用维护

液相色谱法广泛用于食品化工检验、药物研究、生命科学、临床、环境监测等多种领域，其最大的优势是分离混合物中各种组分。承担分离作用的色谱柱是液相色谱系统的核心，决定了分离的效果。本文通过色谱工作者及各大仪器厂商的研究，对分析检测中液相色谱柱的选择及使用维护等相关注意事项进行系统的介绍。     

高效液相色谱法在食品分析中的应用

食品安全问题一直是所有消费者都共同关注的问题,随着利益化的驱动,食品安全问题在近年来越来越突出,检验食品安全成为一项极为重要的程序。高效液相色谱法是食品检测中具有代表性的一种方法,它在食品检测中扮演着重要的角色,具有十分重要的意义。为更好地了解高效液相色谱法在食品安全中的作用,阐述了高效液相色谱在食品分析中的应用。     

高效液相色谱技术在石油化工中的应用

高效液相色谱技术在石油化工生产中的应用是非常广泛的,该技术不仅可以提高化合物分离分析的质量和效率,还可以提高物质测定的准确性,因此该技术的应用对于促进我国石油化工行业的发展具有十分重要的作用。对高效液相色谱技术的特征以及高效液相色谱技术在石油化工生产中的具体应用等几个方面的内容进行了详细地探讨和分析。     

液相色谱-质谱联用法在奶瓶双酚类化合物含量测定中的应用研究

目的:探究液相色谱-质谱联用法在奶瓶双酚类化合物含量测定中的应用。方法:采用标准溶液配制对奶瓶含有的双酚类物质含量进行测定,确保其测定效果的精准性。同时借助0.5 ml 40%的甲醇溶液作为流动相,对样品进行检测分析,观察化合物的分离状况。结果:在液相色谱-质谱联用法优化处理下,奶瓶材料中样品出现明显的分离状况,借助光谱分析仪,发现其整个样品检测的光谱图在线性范围与检出限控制上具有明显的改变,说明样品材料内双酚类化合物含量较高,其对应的样品分离也具有明显的效果。结论:借助液相色谱-质谱联用法能够快速的将奶瓶内双酚类化合物含量测定,其测定精准性具有明显的提高,符合奶瓶食品等检测实践需求。     

高效液相色谱在药物分析中的应用研究进展

高效液相色谱是药物综合分析的常规操作方法。根据药物动力学的规范操作要求,准确的分析药物实际测定的含量和流程。从药物的分析应用方式入手,结合相关的研究思路进行研究,优化相关系统研究的方式操作,重视评估预测推进化管理,制定符合色谱药物分析的方案,结合相关的数据评估方式,提高分析速度、分离效果。按照高效液相色谱的实际规范,需要及时调整色谱的色相变化,对药物进行应用拓展水平的分析,优化超高效液相色谱分析中药物成分的实际应用,提高对超高效液相色谱药物代谢水平的有效应用。     

Sulfite Action in Glycolytic Inhibition: In Vivo Real‐Time Observation by Hyperpolarized 13C NMR Spectroscopy

Detecting the molecular targets of xenobiotic substances in vivo poses a considerable analytical challenge. Here, we describe the use of an NMR‐based tracer methodology for the instantaneous in vivo observation of sulfur(IV) action on cellular metabolism. Specifically, we find that glycolytic flux is directed towards sulfite adducts of dihydroxyacetone phosphate and pyruvate as off‐pathway intermediates that obstruct glycolytic flux. In particular, the pyruvate–sulfite association hinders the formation of downstream metabolites. The apparent in vivo association constant of pyruvate and sulfite agrees with the apparent inhibition constant of CO₂ formation, thus supporting the importance of pyruvate interception in disturbing central metabolism and inhibiting NAD regeneration.     

Aerobic treatment of branched alkylbenzene sulfonates

Branched alkylbenzene sulphonates, recalcitrant xenobiotic compounds, were treated aerobically in a single-tank activated-sludge reactor and also by means of three continuous-stirred-tank reactors (CSTR) in series. For the single-tank reactor it was observed that, the longer the hydraulic retention time, the greater were the reductions in biological oxygen demand (BOD), chemical oxygen demand (COD) and methylene blue active substances (MBAS). Reductions of 80%, 60% and 63% were achieved in the levels of BOD, COD and MBAS, respectively. In the case of the three-CSTR system, acclimatization of the microorganisms was achieved 15 days after start-up. For this system, the reductions in the levels of BOD, COD and MBAS were 80%, 68% and 69%, respectively.     

Electrokinetic extraction of surfactants and heavy metals from sewage sludge

Waste management represents a quite serious problem involving aspects of remediation technologies and potential re-utilization in different fields of human activities. Of course, wastes generated in industrial activities deserve more attention because of the nature and amount of xenobiotic components, often difficult to be eliminated. However, also ordinary wastes of urban origin are drawing more and more attention, depending on the concentration of noxious substances like surfactants and some heavy metal, which may eventually require expensive disposal. In the present paper, a research has been carried out on the application of electrokinetic treatments for the abatement of the above xenobiotic components from sewage sludge generated in urban wastewater treatment plants. Experiments were carried out on a laboratory scale, in a 250 mm × 50 mm × 100 mm cell, using 250-300 g of sludge for each test and current densities between 2.4 and 5.7 mA cm⁻². As a general result, quite significant abatements of heavy-metal ions and surfactants were achieved, with relatively low energy consumption.     

Production of liquid organic substances from the oil shale of the Kotsebinskoe deposit

Two methods are proposed for the production of liquid organic substances from the oil shale of the Kotsebinskoe deposit in Saratov oblast. The areas of possible applications of these organic substances as fuel and additives introduced into organic and mineral matrices.     

Analysis of lipid classes and lipofuscin substances by high performance liquid chromatography

The fractionation and analysis of the lipid classes and fluorescent substances of animal tissues by high performance liquid chromatography (HPLC) using a combination of fluorescence and flame ionization detectors is described. The lipid classes and fluorescent substances are extracted from rat kidney and liver tissue by a new method that involves preextraction of nonlipid and aqueous-soluble fluorescent substances with hot dilute (0.05 N) acetic acid. The lipid classes and organic-soluble fluroscent substances are extracted from the residual tissue in three extractions: the first with chloroform/methanol, 1:1, v/v; the second with chloroform/methanol, 1:2, v/v; and the third with methanol. The fractionation of these compounds by HPLC is carried out with a column 0.2×45 cm, packed with a special adsorbent prepared by reacting silicic acid with ammonium hydroxide. The eluent is passed through a fluorescence detector, which provides a profile of the fluorescent compounds, and then to a flame ionization detector for analysis of the lipid classes. The method is demonstrated on rat blood serum, liver and kidney tissue.     

Exploring Next Generation Probiotics for Metabolic and Microbiota Dysbiosis Linked to Xenobiotic Exposure: Holistic Approach

Variation of gut microbiota in metabolic diseases seems to be related to dysbiosis induced by exposure to multiple substances called Microbiota Disrupting Chemicals (MDCs), which are present as environmental and dietary contaminants. Some recent studies have focused on elucidating the alterations of gut microbiota taxa and their metabolites as a consequence of xenobiotic exposures to find possible key targets involved in the severity of the host disease triggered. Compilation of data supporting the triad of xenobiotic-microbiota-metabolic diseases would subsequently allow such health misbalances to be prevented or treated by identifying beneficial microbe taxa that could be Next Generation Probiotics (NGPs) with metabolic enzymes for MDC neutralisation and mitigation strategies. In this review, we aim to compile the available information and reports focused on variations of the main gut microbiota taxa in metabolic diseases associated with xenobiotic exposure and related microbial metabolite profiles impacting the host health status. We performed an extensive literature search using SCOPUS, Web of Science, and PubMed databases. The data retrieval and thorough analyses highlight the need for more combined metagenomic and metabolomic studies revealing signatures for xenobiotics and triggered metabolic diseases. Moreover, metabolome and microbiome compositional taxa analyses allow further exploration of how to target beneficial NGP candidates according to their alleged variability abundance and potential therapeutic significance. Furthermore, this holistic approach has identified limitations and the need of future directions to expand and integrate key knowledge to design appropriate clinical and interventional studies with NGPs. Apart from human health, the beneficial microbes and metabolites identified could also be proposed for various applications under One Health, such as probiotics for animals, plants and environmental bioremediation.     

Reduction of harmful discharges on contact shielding of liquid media with liquid coatings

Conclusions A formula is given for evaluating the efficiency of using the method of shielding technological solutions. A satisfactory correlation has been found between the calculated and experimental data.Shielding technological solutions makes it possible to reduce losses of toxic and valuable substances in the manufacture of man-made fibres from polymer solutions and in other branches of industry.Translated from Khimicheskie Volokna, No. 5, pp. 47–49, September–October, 1983.     

液质联用技术在化妆品禁用组分测定中的应用

介绍了液质联用分析中的关键技术包括样品前处理技术、常用的质量分析器、基质效应消除方式、定性定量测定等,综述了液质联用技术在化妆品禁用组分测定中的应用,指出目前化妆品中禁用物质的组分检测已从单一成分向多组分发展,更多简单的样品前处理技术,高通量、高分辨率、高准确度的质量分析技术已应用于化妆品禁用组分的检测。     

Structural and Functional Characterization of One Unclassified Glutathione S-Transferase in Xenobiotic Adaptation of Leptinotarsa decemlineata

Arthropod Glutathione S-transferases (GSTs) constitute a large family of multifunctional enzymes that are mainly associated with xenobiotic or stress adaptation. GST-mediated xenobiotic adaptation takes place through direct metabolism or sequestration of xenobiotics, and/or indirectly by providing protection against oxidative stress induced by xenobiotic exposure. To date, the roles of GSTs in xenobiotic adaptation in the Colorado potato beetle (CPB), a notorious agricultural pest of plants within Solanaceae, have not been well studied. Here, we functionally expressed and characterized an unclassified-class GST, LdGSTu1. The three-dimensional structure of the LdGSTu1 was solved with a resolution up to 1.8 Å by X-ray crystallography. The signature motif VSDGPPSL was identified in the “G-site”, and it contains the catalytically active residue Ser14. Recombinant LdGSTu1 was used to determine enzyme activity and kinetic parameters using 1-chloro-2, 4-dinitrobenzene (CDNB), GSH, p-nitrophenyl acetate (PNA) as substrates. The enzyme kinetic parameters and enzyme-substrate interaction studies demonstrated that LdGSTu1 could catalyze the conjugation of GSH to both CDNB and PNA, with a higher turnover number for CDNB than PNA. The LdGSTu1 enzyme inhibition assays demonstrated that the enzymatic conjugation of GSH to CDNB was inhibited by multiple pesticides, suggesting a potential function of LdGSTu1 in xenobiotic adaptation.     

PVC离心母液回用新工艺

介绍了一种PVC母液经处理后可回釜用于聚合生产的新工艺。整个处理过程不需冷却降温,不会引入其他物质,具有运行费用低、生产效益高等优点,在节约助剂的同时,回收了母液中的大部分热量。新工艺适用于各种配方的PVC离心母液。