Pub Date : 2019-09-16DOI: 10.1002/9780470027318.A9412
A. Baker, Martin S. Andersen, C. Marjo, N. Zainuddin, H. Rutlidge, P. W. Graham, R. Henderson
Organic molecules that contain conjugated aromatic constituents have the potential to fluoresce. Both natural and anthropogenic organic matters may contain fluorescent molecules, and river and groundwater organic matters can be understood as a complex mixture of fluorescent and non-fluorescent organic molecules. The investigation of pollution in rivers and groundwaters therefore requires the differentiation of multiple fluorescent molecules from multiple sources. The fluorescence spectra of both natural and pollutant organic matters are increasingly well known. Fluorescent pollutants in rivers and groundwaters are typically identified by high levels of fluorescence in the shortwave ultraviolet spectra associated with high levels of microbiological activity and biochemical oxygen demand (BOD); the presence of polycyclic aromatic hydrocarbons from landfill leachates or petroleum products; or the presence of fluorescent whitening agents (FWAs) from industrial, landfill, or sewerage pollution. These fluorescence signals can be distinguished from natural organic matter fluorescence by analyzing either of the differences in spectral properties, often using multiway analysis such as parallel factor analysis, or the investigation of their sensitivity to microbial or photodegradation. Examples of the investigation of pollution in rivers and groundwaters by fluorescence using both laboratory instrumentation and in situ probes are discussed.
{"title":"Investigation of Pollution in Rivers and Groundwater by Fluorescence","authors":"A. Baker, Martin S. Andersen, C. Marjo, N. Zainuddin, H. Rutlidge, P. W. Graham, R. Henderson","doi":"10.1002/9780470027318.A9412","DOIUrl":"https://doi.org/10.1002/9780470027318.A9412","url":null,"abstract":"Organic molecules that contain conjugated aromatic constituents have the potential to fluoresce. Both natural and anthropogenic organic matters may contain fluorescent molecules, and river and groundwater organic matters can be understood as a complex mixture of fluorescent and non-fluorescent organic molecules. The investigation of pollution in rivers and groundwaters therefore requires the differentiation of multiple fluorescent molecules from multiple sources. The fluorescence spectra of both natural and pollutant organic matters are increasingly well known. Fluorescent pollutants in rivers and groundwaters are typically identified by high levels of fluorescence in the shortwave ultraviolet spectra associated with high levels of microbiological activity and biochemical oxygen demand (BOD); the presence of polycyclic aromatic hydrocarbons from landfill leachates or petroleum products; or the presence of fluorescent whitening agents (FWAs) from industrial, landfill, or sewerage pollution. These fluorescence signals can be distinguished from natural organic matter fluorescence by analyzing either of the differences in spectral properties, often using multiway analysis such as parallel factor analysis, or the investigation of their sensitivity to microbial or photodegradation. Examples of the investigation of pollution in rivers and groundwaters by fluorescence using both laboratory instrumentation and in situ probes are discussed.","PeriodicalId":119970,"journal":{"name":"Encyclopedia of Analytical Chemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127685699","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-09-16DOI: 10.1002/9780470027318.a9691
James G. Longstaffe
{"title":"Nuclear Magnetic Resonance Techniques for Analysis of Contaminants in the Environment","authors":"James G. Longstaffe","doi":"10.1002/9780470027318.a9691","DOIUrl":"https://doi.org/10.1002/9780470027318.a9691","url":null,"abstract":"","PeriodicalId":119970,"journal":{"name":"Encyclopedia of Analytical Chemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128448927","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-06-13DOI: 10.1002/9780470027318.A9917.PUB2
A. Schinkovitz, D. Séraphin, P. Richomme
Mass spectrometry (MS) represents an indispensable tool for the structural identification of natural products (NPs) and is one of the major focus areas of analytical chemistry research. The technique has long been used to obtain molecular weights and further molecular formulae. In the past, former ionization sources such as electronic impact (EI) limited MS analysis to predominately volatile, polar, and thermostable compounds. However, the development of soft ionization techniques such as electrospray ionization (ESI), atmospheric pressure chemical ionization (APCI), and laser desorption/ionization (LDI) have gradually extended the scope of MS analysis to a much wider range of chemical entities. Moreover, the hyphenation of liquid and gas chromatography with MS (LC‐MS, GC‐MS) has provided a most powerful tool for the analysis of complex mixtures and NPs. In fact, LC‐MS is often considered as a method of first choice particularly when studying complex mixtures of small molecules. On the other hand, recent developments in matrix‐assisted laser desorption/ionization (MALDI) and LDI may provide useful supplements and potential alternatives to this approach. Both methods share similar, though slightly different ionization mechanisms. While MALDI uses small molecules comprising strong UV chromophores (matrices) to transfer laser energy to the sample material, LDI targets compounds that can be directly ionized by laser irradiation without any matrix support. Moreover, certain compounds showing LDI properties may also work as MALDI matrices. With regard to NPs research, MALDI and LDI may help overcoming certain limitations encountered in LC‐MS such as the indispensable use of buffer solutions when analyzing alkaloids. Moreover, as (MA)LDI hardly requires any sample conditioning, analysis time can be significantly shortened. With all this in mind, the subsequent article will highlight some interesting MALDI and LDI applications, which focus on the detection of NPs in complex mixtures. This includes the use of specifically adapted matrices for the selective detection of alkaloids (i), the study of the inherent LDI and matrix properties of phenolic compounds (ii) as well of evaluation on the reproducibility of LDI signal patterns (iii). Eventually, a statistical approach toward LDI profiling, which may provide a future tool for quality control of large sample batches will be presented (iv).
{"title":"New Developments of Laser Desorption Ionization Mass Spectrometry in Natural Products Research","authors":"A. Schinkovitz, D. Séraphin, P. Richomme","doi":"10.1002/9780470027318.A9917.PUB2","DOIUrl":"https://doi.org/10.1002/9780470027318.A9917.PUB2","url":null,"abstract":"Mass spectrometry (MS) represents an indispensable tool for the structural identification of natural products (NPs) and is one of the major focus areas of analytical chemistry research. The technique has long been used to obtain molecular weights and further molecular formulae. In the past, former ionization sources such as electronic impact (EI) limited MS analysis to predominately volatile, polar, and thermostable compounds. However, the development of soft ionization techniques such as electrospray ionization (ESI), atmospheric pressure chemical ionization (APCI), and laser desorption/ionization (LDI) have gradually extended the scope of MS analysis to a much wider range of chemical entities. Moreover, the hyphenation of liquid and gas chromatography with MS (LC‐MS, GC‐MS) has provided a most powerful tool for the analysis of complex mixtures and NPs. In fact, LC‐MS is often considered as a method of first choice particularly when studying complex mixtures of small molecules. On the other hand, recent developments in matrix‐assisted laser desorption/ionization (MALDI) and LDI may provide useful supplements and potential alternatives to this approach. Both methods share similar, though slightly different ionization mechanisms. While MALDI uses small molecules comprising strong UV chromophores (matrices) to transfer laser energy to the sample material, LDI targets compounds that can be directly ionized by laser irradiation without any matrix support. Moreover, certain compounds showing LDI properties may also work as MALDI matrices. With regard to NPs research, MALDI and LDI may help overcoming certain limitations encountered in LC‐MS such as the indispensable use of buffer solutions when analyzing alkaloids. Moreover, as (MA)LDI hardly requires any sample conditioning, analysis time can be significantly shortened. With all this in mind, the subsequent article will highlight some interesting MALDI and LDI applications, which focus on the detection of NPs in complex mixtures. This includes the use of specifically adapted matrices for the selective detection of alkaloids (i), the study of the inherent LDI and matrix properties of phenolic compounds (ii) as well of evaluation on the reproducibility of LDI signal patterns (iii). Eventually, a statistical approach toward LDI profiling, which may provide a future tool for quality control of large sample batches will be presented (iv).","PeriodicalId":119970,"journal":{"name":"Encyclopedia of Analytical Chemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114883756","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-06-13DOI: 10.1002/9780470027318.A9674
T. Gräwert, D. Svergun
{"title":"Application of Small‐Angle X‐Ray Scattering in Studies of Biological Macromolecules","authors":"T. Gräwert, D. Svergun","doi":"10.1002/9780470027318.A9674","DOIUrl":"https://doi.org/10.1002/9780470027318.A9674","url":null,"abstract":"","PeriodicalId":119970,"journal":{"name":"Encyclopedia of Analytical Chemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130156109","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-06-13DOI: 10.1002/9780470027318.A9278.PUB2
Kirsty F. Gibson, S. Kazarian, S. Kharintsev
{"title":"Tip‐Enhanced\u0000 R\u0000 aman Spectroscopy","authors":"Kirsty F. Gibson, S. Kazarian, S. Kharintsev","doi":"10.1002/9780470027318.A9278.PUB2","DOIUrl":"https://doi.org/10.1002/9780470027318.A9278.PUB2","url":null,"abstract":"","PeriodicalId":119970,"journal":{"name":"Encyclopedia of Analytical Chemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132643676","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-06-13DOI: 10.1002/9780470027318.a9392.pub2
R. C. Torrijos, I. G. Mariño, R. M. Goyanes, José B. Quintana Álvarez, María Ramil Criado, Maxi Rodríguez, I. Rodríguez Pereiro
{"title":"Sample Preparation Strategies for Analytical Determinations","authors":"R. C. Torrijos, I. G. Mariño, R. M. Goyanes, José B. Quintana Álvarez, María Ramil Criado, Maxi Rodríguez, I. Rodríguez Pereiro","doi":"10.1002/9780470027318.a9392.pub2","DOIUrl":"https://doi.org/10.1002/9780470027318.a9392.pub2","url":null,"abstract":"","PeriodicalId":119970,"journal":{"name":"Encyclopedia of Analytical Chemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114349834","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-06-13DOI: 10.1002/9780470027318.A9291
R. Michalski, M. Jabłońska-Czapla, Aleksandra Łyko, S. Szopa
Speciation analysis, understood as research into various element forms, is gaining importance in environmental protection, biochemistry, geology, medicine, pharmacy, and food quality control. It is popular because what frequently determines the toxicological properties of a compound or element is not its total content. In many cases, it is the presence of its various forms. Studying low analyte concentrations, particularly in complex matrix samples, requires meticulous and sophisticated analytical techniques. The latest trends embrace the so-called hyphenated methods, which combine different separation and detection methods. The following article describes the role and importance of hyphenated methods in speciation analyses of selected elements.
{"title":"Hyphenated Methods for Speciation Analysis","authors":"R. Michalski, M. Jabłońska-Czapla, Aleksandra Łyko, S. Szopa","doi":"10.1002/9780470027318.A9291","DOIUrl":"https://doi.org/10.1002/9780470027318.A9291","url":null,"abstract":"Speciation analysis, understood as research into various element forms, is gaining importance in environmental protection, biochemistry, geology, medicine, pharmacy, and food quality control. It is popular because what frequently determines the toxicological properties of a compound or element is not its total content. In many cases, it is the presence of its various forms. Studying low analyte concentrations, particularly in complex matrix samples, requires meticulous and sophisticated analytical techniques. The latest trends embrace the so-called hyphenated methods, which combine different separation and detection methods. The following article describes the role and importance of hyphenated methods in speciation analyses of selected elements.","PeriodicalId":119970,"journal":{"name":"Encyclopedia of Analytical Chemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133948919","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-06-13DOI: 10.1002/9780470027318.A9670
C. Breeding, S. eaton-magaña
{"title":"Fluorescence of Natural and Synthetic Gem Diamond: Mechanism and Applications","authors":"C. Breeding, S. eaton-magaña","doi":"10.1002/9780470027318.A9670","DOIUrl":"https://doi.org/10.1002/9780470027318.A9670","url":null,"abstract":"","PeriodicalId":119970,"journal":{"name":"Encyclopedia of Analytical Chemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124873531","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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