Biosensors as useful tools for environmental analysis and monitoring

Recent advances in the development and application of biosensors for environmental analysis and monitoring are reviewed in this article. Several examples of biosensors developed for relevant environmental pollutants and parameters are briefly overviewed. Special attention is paid to the application of biosensors to real environmental samples, taking into consideration aspects such as sample pretreatment, matrix effects and validation of biosensor measurements. Current trends in biosensor development are also considered and commented on in this work. In this context, nanotechnology, miniaturisation, multi-sensor array development and, especially, biotechnology arise as fast-growing areas that will have a marked influence on the development of new biosensing strategies in the near future.     

环境监测分析中标准物质的选择及应用

针对分析人员对标准物质概念不清、使用不规范等问题,就环境监测领域标准物质选择和应用方法做了梳理。从标准物质的概念、区分有证和非有证标准物质的方法、标准物质的应用范围及标准物质的使用注意事项等4个方面系统地进行了梳理,重点阐述了有证标准物质和非有证标准物质的概念区别及使用时的误区,为分析人员在实际工作中出具准确数据提供理论依据。     

Flow injection spectrophotometric analysis of lead in human saliva for monitoring environmental pollution

A new highly sensitive, simple and low-cost methodology for the direct determination of Pb (II) with 2-(5-bromo-2-pyridylazo)-5-dimethylaminophenol in ethanolic medium has been developed. The absorption spectroscopy of the complex has been examined in detail, and the chemical variables affecting the sensitivity of procedure studied, optimized and applied to the determination of trace amounts of lead in human saliva. Under the optimal experimental conditions, a precision of 1.61x10(-4) mug cm(-2) was achieved, the molar absorptivity being (epsilon) 5.6x10(4) l mol(-1) cm(-1). An FI technique is proposed, and it is possible to determine trace levels of lead by injection into a steam buffered at pH 7.15, containing 70% ethanol: 30% Tris buffer 3.5x10(-3) mol l(-1) (pH=7.2), 1x10(-4) mol l(-1) 5-BrDMPAP. The FIA configuration allows the analysis of 45 samples per hour. The lower limit of detection (LOD) was 1x10(-7) mol l(-1). The calibration plot was linear at least within two orders of magnitude of lead concentration. The use of an HPLC pump for the FI analysis led to a substantial improvement in the analytical performance of the method, which clearly satisfies the typical requirements for control processes.     

The preparation of a cabbage reference material for environmental monitoring and food analysis

 Cabbage is frequently used in environmental monitoring and food control, and, hence, cabbage reference materials (RMs) are required for ensuring quality assurance. A cabbage RM was prepared in view of certification of specific elements from the "black list" of high toxicological interest and nutritive importance. All tasks of the RM production (production of the plant material, cutting and freeze-drying, determination of the residual water content, preparation of the RM, homogeneity testing, stability testing, certification measurements) are described in detail. Received: 12 November 1999 / Accepted: 29 January 2000     

Nanoparticles in electrochemical sensors for environmental monitoring

We review the state-of-the-art application of nanoparticles (NPs) in electrochemical analysis of environmental pollutants. We summarize methods for preparing NPs and modifying electrode surfaces with NPs. We describe several examples of applications in environmental electrochemical sensors and performance in terms of sensitivity and selectivity for both metal and metal-oxide NPs. We present recent trends in the beneficial use of NPs in constructing electrochemical sensors for environmental monitoring and discuss future challenges.NPs have promising potential to increase competitiveness of electrochemical sensors in environmental monitoring, though research has focused mainly on development of methodology for fabricating new sensors, and the number of studies for optimizing the performance of sensors and the applicability to real samples is still limited.     

Lab-on-a-chip systems for biomedical and environmental monitoring

During the last decade, pocket-sized analytical equipment based on the lab-on-a-chip approach has become available. These chips, in combination with portable electronic equipment, are applicable in, for example, point-of-care ion analysis of body fluids, forensics, identification of explosives, tracking of pollution in environmental or waste waters, monitoring nutrients in agricultural or horticultural water, controlling quality in food production, or process control in chemical industry. This paper discusses several demonstrator systems with applications in these fields.     

Analytical procedures for environmental and biological monitoring

Summary Health protection of persons exposed to chemical substances is achieved by limitation and supervision of the concentrations a) of substances in the air (Environmental Monitoring, EM) and b) of substances and metabolites in body fluids (Biological Monitoring, BM). Both strategies belong to the sphere of responsibility of the analytical chemist. EM and BM show requirements which are different in some characteristic facts among them: EM. The assessment of exposure is difficult because the concentrations strongly depend on the location and time of measurement. The analytical determination of ppm and ppb concentrations in the air in general do not make problems nowadays. Unsolved, however, is the problem of the quality control and the determination of certain species of substances. BM. It offers a better means of the assessment of individual exposure. The complexity of the biological matrix, its low availability, and the small concentration of substances are still a great problem for analytical chemistry. Nowadays g/l-concentrations of metals, organic solvents etc. can routinely be determined in biological matrices. Efficiency of analytical chemistry, however, must further be improved. Certain substances, for instance PAH's, certain metals like Pt, Ni, Co cannot be determined in the required range of concentrations. Huge efforts have to be done to determine the substances at the location of their effects for instance bound to DNA, Hb or certain proteins.The possibilities and limitations of instrumental analysis in the field of environmental and occupational health are discussed using characteristic examples. The problems of analytical reliability and the comparability of results are also discussed.Dedicated to Prof. Dr. G. Tölg, Dortmund, on the occasion of his 60th birthday     

Isotopic analysis for degradation diagnosis of calcite matrix in mortar

Mortar that was used in building as well as in conservation and restoration works of wall paintings have been analysed isotopically (δ¹³C and δ¹⁸O) in order to evaluate the setting environments and secondary processes, to distinguish the structural components used and to determine the exact causes that incurred the degradation phenomena. The material undergoes weathering and decay on a large proportion of its surface and in depth, due to the infiltration of water through the structural blocks. Mineralogical analysis indicated signs of sulphation and dissolution/recrystallisation processes taking place on the material, whereas stable isotopes provided information relative to the origin of the CO₂ and water during calcite formation and degradation processes. Isotopic change of the initial δ¹³C and δ¹⁸O in carbonate matrix was caused by alteration of the primary source of CO₂ and H₂O in mortar over time, particularly by recrystallisation of calcite with porewater, evaporated or re-condensed water, and CO₂ from various sources of atmospheric and biogenic origin. Human influence (surface treatment) and biological growth (e.g. fungus) are major exogenic processes which may alter δ¹⁸O and δ¹³C in lime mortar.     

Performance analysis of different methods to determine 131I in water samples for environmental monitoring

Journal of Radioanalytical and Nuclear Chemistry - There are different standard procedures to measure 131I concentration in water samples. For environmental monitoring purposes the best...     

Electrochemical methods for monitoring of environmental carcinogens

The use of modern electroanalytical techniques, namely differential pulse polarography, differential pulse voltammetry on hanging mercury drop electrode or carbon paste electrode, adsorptive stripping voltammetry and high performance liquid chromatography with electrochemical detection for the determination of trace amounts of carcinogenic N-nitroso compounds, azo compounds, heterocyclic compounds, nitrated polycyclic aromatic hydrocarbons and aromatic and heterocyclic amines is discussed. Scope and limitations of these methods are described and some practical applications based on their combination with liquid-liquid or solid phase extraction are given.     

Recent advances in biosensor techniques for environmental monitoring

Biosensors for environmental applications continue to show advances and improvements in areas such as sensitivity, selectivity and simplicity. In addition to detecting and measuring specific compounds or compound classes such as pesticides, hazardous industrial chemicals, toxic metals, and pathogenic bacteria, biosensors and bioanalytical assays have been designed to measure biological effects such as cytotoxicity, genotoxicity, biological oxygen demand, pathogenic bacteria, and endocrine disruption effects. This article is intended to discuss recent advances in the area of biosensors for environmental applications.     

New spectroscopic methods for environmental measurement and monitoring

The ability to monitor a broad range of chemical species in the atmosphere, geosphere, and hydrosphere is a key technology for addressing global environmental issues. This report surveys several high sensitivity spectroscopic techniques for this purpose, including Frequency-Modulation-Enhanced Remote Sensing, In-traCavity Laser Absorption Spectroscopy, Cavity RingDown Spectroscopy, and Raman Spectroscopy.     

Multiplex bioanalytical methods for food and environmental monitoring

Recent advances in miniaturization of analytical systems and newly emerging technologies offer platforms with greater automation and multiplexing capabilities than traditional biological binding assays. Multiplexed bioanalytical techniques provide control agencies and food industries with new possibilities for improved, more efficient monitoring of food and environmental contaminants. This review deals with recent developments in planar-array and suspension-array technologies, and their applications in detecting pathogens, food allergens and adulterants, toxins, antibiotics and environmental contaminants.     

Fluorescence spectroscopy for monitoring deterioration of extra virgin olive oil during heating

The potential of fluorescence spectroscopy for characterizing the deterioration of extra virgin olive oil (EVOO) during heating was investigated. Two commercial EVOO were analysed by HPLC to determine changes in EVOO vitamin E and polyphenols as a result of heating at 170°C for 3 h. This thermal oxidation of EVOO caused an exponential decrease in hydroxytyrosol and vitamin E (R²=0.90 and 0.93, respectively) whereas the tyrosol content was relatively stable. At the same time, amounts of preformed hydroperoxides (ROOH), analysed by an indirect colorimetric method, decreased exponentially during the heating process (R²=0.94), as a result of their degradation into secondary peroxidation products. Fluorescence excitation spectra with emission at 330 and 450 nm were recorded to monitor polyphenols and vitamin E evolution and ROOH degradation, respectively. Partial least-squares calibration models were built to predict these indicators of EVOO quality from oil fluorescence spectra. A global approach was then proposed to monitor the heat charge from the overall fluorescence fingerprint. Different data pretreatment methods were tested. This study indicates that fluorescence spectroscopy is a promising, rapid, and cost-effective approach for evaluating the quality of heat-treated EVOO, and is an alternative to time-consuming conventional analyses. In future work, calibration models will be developed using a wide range of EVOO samples.     

混凝土中钢筋的腐蚀行为研究

本文探讨了在不同 pH和Cl- 含量的模拟混凝土孔隙液介质中 ,混凝土中钢筋的腐蚀电化学行为 .电化学技术测试结果表明 ,正常情况下 ,钢筋在混凝土中受到高碱性环境的保护 ,耐蚀性好 .但随着介质 pH的降低、Cl- 含量的上升 ,钢筋腐蚀电流升高 ;动电位阳极极化曲线的测试表明 ,钢筋的维钝电流增大 ,击穿电位负移 ,混凝土中钢筋的耐蚀性下降 .这是钢筋表面钝性受破坏的缘故 .     

Corrosion of stainless steel in food and pharmaceutical industry

Stainless steels are widely used in the food and pharmaceutical industry because of their high corrosion resistance and superior mechanical properties. These features are crucial because produced foodstuffs and drugs must comply with high purity and quality standards. Just a proper selection of stainless steel grade can prevent corrosion phenomena that can be detrimental to the whole manufacturing process. Food/drugs production process phases will be here analyzed and discussed with a particular emphasis on the possible corrosion mechanism of stainless steels in those particular operating conditions. Recent advances on the methods to assess corrosion of stainless steels in food and pharmaceutical industries will be disclosed.     

色谱技术在环境分析中的应用 引言

快速、灵敏、准确的检测技术是环境科学研究的基础,从环境污染物种类和形态的鉴定、浓度的检测、污染源的判别,到国内各区域、全国乃至全球性环境问题的认识与解决,无不依赖于环境分析化学的发展。色谱技术的进步在环境分析化学与环境监测的发展进程中起到了重要的推动作用。据统计,在目前的环境监测方法中,色谱分析方法所占的比率超过了60%,全二维色谱技术、色谱与串联质谱联用技术等在环境分析中的应用大大提高了复杂污染物检测的灵敏度和准确性。 为了集中展示我国科研和环境监测人员在环境分析与环境监测方面的最新成果,《色谱》特此出版“色谱技术在环境分析中的应用”专栏。我们有幸邀请到活跃在环境分析与环境监测领域的专家、学者撰写相关学术论文和综述。本专栏的文章中既有资深学者高屋建瓴的综述,也有来自环境监测一线的监测案例分析。开发新型环境污染物的检测技术是本专栏的重点内容。随着化学工业的发展以及人们对环境质量要求的提高,尚未列入法规监管的新型污染物日益增多,新型污染物所引发的环境问题愈发严重,开发并完善新型污染物的检测方法是环境保护重要的基础性和前沿性工作。本专栏汇集了目前受到高度关注的新型污染物如全氟化合物、药物、饮用水消毒副产物、溴代阻燃剂等的色谱分析方法,希望这些方法能在今后的环境监管中发挥作用。另外,我国的环境监测已逐渐从常量、微量分析向痕量、超痕量分析方向发展,同位素稀释色谱-质谱联用技术是测定痕量污染物准确度最好的方法,然而同位素稀释方法除了应用于二恶英类污染物的分析外,尚未列入我国的环境监测技术标准体系,方法的应用还很少。本专栏发表了有关同位素稀释色谱-质谱联用测定有机污染物的论文,其中包括具有很大技术挑战的同位素稀释色谱-质谱联用检测毒杀芬的方法,相信今后同位素稀释技术会在我国环境监测中得到发展和普及。 由于本专栏的容量有限,因此所刊登的论文还不足以涵盖色谱技术在我国环境分析领域应用的全貌,但我们还是希望读者能从本专栏的文章中受到启发,从而不断提高我国环境分析研究与应用的水平。我们不仅期待环境分析的新技术和新方法,也期待我国环境监测技术标准的更新换代。事实将会进一步证明,色谱技术在环境分析中大有可为,环境分析的新技术将对提高我国环境监管水平发挥更大的作用。     

Progress in the realisation of an autonomous environmental monitoring device for ammonia

Progress in the development of a micro-fluidic system for colorimetric monitoring of ammonia in drinking and wastewater is described. The ultimate goal is to have a miniaturised instrument that can produce accurate, reliable measurements, is easy to operate, has minimal power consumption, and can operate autonomously for a year. In this study, the indophenol reaction is incorporated into a simple, reliable analytical micro-fluidic system. Absorbance measurements for the blue ammonia-indophenol complex formed in the micro-fluidic system are shown. A key issue is the limiting stability of hypochlorite, a reagent used in the assay. The effects of hypochlorite concentration and impurities on the stability of hypochlorite are investigated and discussed. Decomposition is shown to be very dependent on the presence of heavy-metal impurities. With low levels of these catalytic metals and careful storage, hypochlorite has been shown to be stable for over a year.