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Víctor Cerdà - One of the best experts on this subject based on the ideXlab platform.

  • Chapter 6 – Software
    Flow Analysis, 2014
    Co-Authors: Víctor Cerdà, Jessica Avivar, Laura Ferrer, A. Cerdà
    Abstract:

    Computer advances have played a major role in Flow techniques development. On the one hand, one of the greatest hindrances to the development of Flow techniques other than Segmented Flow Analysis and Flow injection Analysis (FIA) was the lack of interfaces to control the analytical equipment via a computer. Most Flow techniques require computer control, but FIA which has the invaluable advantage of using very simple assemblies that are easy to control manually. This provided popularity and widespread success to this technique, immediately after its inception. By contrast, the need for computer control in sequential injection Analysis (SIA) and other multicommutated Flow techniques, and the lack of experience in connecting computers to instruments at the time it was developed delayed its success. On the other hand, advances in information technology have provided most salient Flow techniques' benefits, such as fully automation, autonomy, precision and accuracy. Therefore, advances in more recent techniques such as SIA, multicommutated Flow Analysis, multisyringe Flow injection Analysis and lab on valve, and their combinations, have relied on the availability of appropriate dedicated software for their control.

  • Laboratory automation based on Flow techniques
    Pure and Applied Chemistry, 2012
    Co-Authors: Víctor Cerdà, Jessica Avivar, A. Cerdà
    Abstract:

    Flow techniques have undoubtedly aroused special interest in relation to many other automatic methodologies of Analysis. Ever since Segmented Flow Analysis (SFA) was developed by Skeggs in 1957, Flow techniques have been in continuous evolution toward new develop ments. There is no solid argument in favor of using any particular Flow technique sep- arately; rather, substantial advantages can be derived from their combination. Since Flow- based methods are nonseparative tools, the advantages of combining Flow techniques with separation techniques are noteworthy. High selectivity can be achieved by coupling them with liquid chromatography (LC), gas chromatography (GC), solid-phase extraction (SPE), or capillary electrophoresis (CE). Thus, a detailed description of Flow techniques, their evo- lution, their hyphenation advantages, and a critical comparison between current developed methods exploiting Flow techniques aimed at solving present analytical needs are reviewed in this article.

  • Flow Analysis techniques for phosphorus: an overview
    Talanta, 2005
    Co-Authors: José Manuel Estela, Víctor Cerdà
    Abstract:

    A bibliographical review on the implementation and the results obtained in the use of different Flow analytical techniques for the determination of phosphorus is carried out. The sources, occurrence and importance of phosphorus together with several aspects regarding the Analysis and terminology used in the determination of this element are briefly described. A classification as well as a brief description of the basis, advantages and disadvantages of the different existing Flow techniques, namely; Segmented Flow Analysis (SFA), Flow injection Analysis (FIA), sequential injection Analysis (SIA), all injection Analysis (AIA), batch injection Analysis (BIA), multicommutated FIA (MCFIA), multisyringe FIA (MSFIA) and multipumped FIA (MPFIA) is also carried out. The most relevant manuscripts regarding the Analysis of phosphorus by means of Flow techniques are herein classified according to the detection instrumental technique used with the aim to facilitate their study and obtain an overall scope. Finally, the analytical characteristics of numerous Flow-methods reported in the literature are provided in the form of a table and their applicability to samples with different matrixes, namely water samples (marine, river, estuarine, waste, industrial, drinking, etc.), soils leachates, plant leaves, toothpaste, detergents, foodstuffs (wine, orange juice, milk), biological samples, sugars, fertilizer, hydroponic solutions, soils extracts and cyanobacterial biofilms are tabulated.

  • application of Flowing stream techniques to water Analysis part iii metal ions alkaline and alkaline earth metals elemental and harmful transition metals and multielemental Analysis
    Talanta, 2004
    Co-Authors: Manuel Miró, José Manuel Estela, Víctor Cerdà
    Abstract:

    In the earlier parts of this series of reviews [1,2], the most relevant Flowing stream techniques (namely, Segmented Flow Analysis, continuous Flow Analysis, Flow injection (FI) Analysis, sequential injection (SI) Analysis, multicommuted Flow injection Analysis and multisyringe Flow injection Analysis) applied to the determination of several core inorganic parameters for water quality assessment, such as nutrients and anionic species including nitrogen, sulfur and halogen compounds, were described. In the present paper, Flow techniques are presented as powerful analytical tools for the environmental monitoring of metal ions (alkaline and alkaline-earth metals, and elemental and harmful transition metals) as well as to perform both multielemental and speciation Analysis in water samples. The potentials of Flow techniques for automated sample treatment involving on-line analyte separation and/or pre-concentration are also discussed in the body of the text, and demonstrated for each individual ion with a variety of strategies successfully applied to trace Analysis. In this context, the coupling of Flow methodologies with atomic spectrometric techniques such as flame atomic absorption spectrometry (FAAS), electrothermal atomic absorption spectrometry (ETAAS), inductively coupled plasma mass spectrometry (ICPMS) or hydride-generation (HG)/cold-vapor (CV) approaches, launching the so-called hyphenated techniques, is specially worth mentioning.

  • Application of Flowing-stream techniques to water Analysis Part II. General quality parameters and anionic compounds: halogenated, sulphur and metalloid species.
    Talanta, 2004
    Co-Authors: Manuel Miró, José Manuel Estela, Víctor Cerdà
    Abstract:

    In the first part of this review [Talanta 60 (2000) 867], Flowing-stream methods (namely, Segmented Flow Analysis (SFA), continuous-Flow Analysis (CFA), Flow-injection Analysis (FIA), sequential-injection Analysis (SIA), multicommuted Flow-injection Analysis (MCFIA) and multisyringe Flow-injection Analysis (MSFIA)) were presented as powerful analytical tools for nutrient determination in water samples when coupled to photometric/fluorimetric detection, Flow-through ion-selective electrodes or amperometric sensors. In the present paper, relevant Flow methods applied to the monitoring of anionic species as well as to the determination of general parameters for water quality evaluation (such as pH, alkalinity, chemical and biochemical oxygen demand, conductivity and total ionic content) are reviewed, and their background, detection technique and noteworthy analytical features are detailed. Furthermore, other techniques, such as Flow systems connected to hydride-generation atomic absorption spectrometry, should be highlighted as practical approaches for metalloid determination since a series of speciation schemes are demonstrated to be readily adaptable.

José Manuel Estela - One of the best experts on this subject based on the ideXlab platform.

  • Flow Analysis techniques for phosphorus: an overview
    Talanta, 2005
    Co-Authors: José Manuel Estela, Víctor Cerdà
    Abstract:

    A bibliographical review on the implementation and the results obtained in the use of different Flow analytical techniques for the determination of phosphorus is carried out. The sources, occurrence and importance of phosphorus together with several aspects regarding the Analysis and terminology used in the determination of this element are briefly described. A classification as well as a brief description of the basis, advantages and disadvantages of the different existing Flow techniques, namely; Segmented Flow Analysis (SFA), Flow injection Analysis (FIA), sequential injection Analysis (SIA), all injection Analysis (AIA), batch injection Analysis (BIA), multicommutated FIA (MCFIA), multisyringe FIA (MSFIA) and multipumped FIA (MPFIA) is also carried out. The most relevant manuscripts regarding the Analysis of phosphorus by means of Flow techniques are herein classified according to the detection instrumental technique used with the aim to facilitate their study and obtain an overall scope. Finally, the analytical characteristics of numerous Flow-methods reported in the literature are provided in the form of a table and their applicability to samples with different matrixes, namely water samples (marine, river, estuarine, waste, industrial, drinking, etc.), soils leachates, plant leaves, toothpaste, detergents, foodstuffs (wine, orange juice, milk), biological samples, sugars, fertilizer, hydroponic solutions, soils extracts and cyanobacterial biofilms are tabulated.

  • application of Flowing stream techniques to water Analysis part iii metal ions alkaline and alkaline earth metals elemental and harmful transition metals and multielemental Analysis
    Talanta, 2004
    Co-Authors: Manuel Miró, José Manuel Estela, Víctor Cerdà
    Abstract:

    In the earlier parts of this series of reviews [1,2], the most relevant Flowing stream techniques (namely, Segmented Flow Analysis, continuous Flow Analysis, Flow injection (FI) Analysis, sequential injection (SI) Analysis, multicommuted Flow injection Analysis and multisyringe Flow injection Analysis) applied to the determination of several core inorganic parameters for water quality assessment, such as nutrients and anionic species including nitrogen, sulfur and halogen compounds, were described. In the present paper, Flow techniques are presented as powerful analytical tools for the environmental monitoring of metal ions (alkaline and alkaline-earth metals, and elemental and harmful transition metals) as well as to perform both multielemental and speciation Analysis in water samples. The potentials of Flow techniques for automated sample treatment involving on-line analyte separation and/or pre-concentration are also discussed in the body of the text, and demonstrated for each individual ion with a variety of strategies successfully applied to trace Analysis. In this context, the coupling of Flow methodologies with atomic spectrometric techniques such as flame atomic absorption spectrometry (FAAS), electrothermal atomic absorption spectrometry (ETAAS), inductively coupled plasma mass spectrometry (ICPMS) or hydride-generation (HG)/cold-vapor (CV) approaches, launching the so-called hyphenated techniques, is specially worth mentioning.

  • Application of Flowing-stream techniques to water Analysis Part II. General quality parameters and anionic compounds: halogenated, sulphur and metalloid species.
    Talanta, 2004
    Co-Authors: Manuel Miró, José Manuel Estela, Víctor Cerdà
    Abstract:

    In the first part of this review [Talanta 60 (2000) 867], Flowing-stream methods (namely, Segmented Flow Analysis (SFA), continuous-Flow Analysis (CFA), Flow-injection Analysis (FIA), sequential-injection Analysis (SIA), multicommuted Flow-injection Analysis (MCFIA) and multisyringe Flow-injection Analysis (MSFIA)) were presented as powerful analytical tools for nutrient determination in water samples when coupled to photometric/fluorimetric detection, Flow-through ion-selective electrodes or amperometric sensors. In the present paper, relevant Flow methods applied to the monitoring of anionic species as well as to the determination of general parameters for water quality evaluation (such as pH, alkalinity, chemical and biochemical oxygen demand, conductivity and total ionic content) are reviewed, and their background, detection technique and noteworthy analytical features are detailed. Furthermore, other techniques, such as Flow systems connected to hydride-generation atomic absorption spectrometry, should be highlighted as practical approaches for metalloid determination since a series of speciation schemes are demonstrated to be readily adaptable.

  • Application of Flowing stream techniques to water Analysis. Part I. Ionic species: dissolved inorganic carbon, nutrients and related compounds.
    Talanta, 2003
    Co-Authors: Manuel Miró, José Manuel Estela, Víctor Cerdà
    Abstract:

    This paper summarizes the most relevant manuscripts issued from 1990 to date referred to water Analysis using Flowing stream techniques. Concretely, reported Flow methods applied to the determination or monitoring of inorganic analytes (viz. carbon, nitrogen, phosphorous and silicon species) together with some related compounds to assess water quality in drinking, rain, underground, marine, river, estuarine, waste and industrial samples are reviewed. For the first time, the most widespread Flow techniques of Analysis described in the literature (viz. Segmented Flow Analysis (SFA), continuous Flow Analysis (CFA), Flow injection Analysis (FIA), sequential injection Analysis (SIA), multicommuted FIA (MCFIA), multisyringe FIA (MSFIA), along with the different exploited injection modalities are included in the same review.

  • Flow techniques in water Analysis.
    Talanta, 1999
    Co-Authors: Víctor Cerdà, José Manuel Estela, R. Forteza, Andreu Cladera, Eduardo Becerra, P Altimira, P Sitjar
    Abstract:

    In the present work the main Flow techniques for the Analysis and monitoring of several parameters of interest in the quality control of different types of waters are reviewed. Firstly, a review involving the advantages and disadvantages of Flow techniques, from those currently out-dated, such as Segmented Flow Analysis (SFA), to the most modern techniques, such as Flow injection Analysis (FIA), sequential injection Analysis (SIA) and multi-commutation techniques (MCFA), is carried out. On the other hand, a new technique, the multi-syringe Flow Analysis (MSFA) is hereby described for the first time as both a fast and robust alternative. Its possibilities, limitations and potential advantages when using this technique either on its own or coupled to SIA, which carries out a previous sample handling, are outlined.

Manuel Miró - One of the best experts on this subject based on the ideXlab platform.

  • application of Flowing stream techniques to water Analysis part iii metal ions alkaline and alkaline earth metals elemental and harmful transition metals and multielemental Analysis
    Talanta, 2004
    Co-Authors: Manuel Miró, José Manuel Estela, Víctor Cerdà
    Abstract:

    In the earlier parts of this series of reviews [1,2], the most relevant Flowing stream techniques (namely, Segmented Flow Analysis, continuous Flow Analysis, Flow injection (FI) Analysis, sequential injection (SI) Analysis, multicommuted Flow injection Analysis and multisyringe Flow injection Analysis) applied to the determination of several core inorganic parameters for water quality assessment, such as nutrients and anionic species including nitrogen, sulfur and halogen compounds, were described. In the present paper, Flow techniques are presented as powerful analytical tools for the environmental monitoring of metal ions (alkaline and alkaline-earth metals, and elemental and harmful transition metals) as well as to perform both multielemental and speciation Analysis in water samples. The potentials of Flow techniques for automated sample treatment involving on-line analyte separation and/or pre-concentration are also discussed in the body of the text, and demonstrated for each individual ion with a variety of strategies successfully applied to trace Analysis. In this context, the coupling of Flow methodologies with atomic spectrometric techniques such as flame atomic absorption spectrometry (FAAS), electrothermal atomic absorption spectrometry (ETAAS), inductively coupled plasma mass spectrometry (ICPMS) or hydride-generation (HG)/cold-vapor (CV) approaches, launching the so-called hyphenated techniques, is specially worth mentioning.

  • Application of Flowing-stream techniques to water Analysis Part II. General quality parameters and anionic compounds: halogenated, sulphur and metalloid species.
    Talanta, 2004
    Co-Authors: Manuel Miró, José Manuel Estela, Víctor Cerdà
    Abstract:

    In the first part of this review [Talanta 60 (2000) 867], Flowing-stream methods (namely, Segmented Flow Analysis (SFA), continuous-Flow Analysis (CFA), Flow-injection Analysis (FIA), sequential-injection Analysis (SIA), multicommuted Flow-injection Analysis (MCFIA) and multisyringe Flow-injection Analysis (MSFIA)) were presented as powerful analytical tools for nutrient determination in water samples when coupled to photometric/fluorimetric detection, Flow-through ion-selective electrodes or amperometric sensors. In the present paper, relevant Flow methods applied to the monitoring of anionic species as well as to the determination of general parameters for water quality evaluation (such as pH, alkalinity, chemical and biochemical oxygen demand, conductivity and total ionic content) are reviewed, and their background, detection technique and noteworthy analytical features are detailed. Furthermore, other techniques, such as Flow systems connected to hydride-generation atomic absorption spectrometry, should be highlighted as practical approaches for metalloid determination since a series of speciation schemes are demonstrated to be readily adaptable.

  • Application of Flowing stream techniques to water Analysis. Part I. Ionic species: dissolved inorganic carbon, nutrients and related compounds.
    Talanta, 2003
    Co-Authors: Manuel Miró, José Manuel Estela, Víctor Cerdà
    Abstract:

    This paper summarizes the most relevant manuscripts issued from 1990 to date referred to water Analysis using Flowing stream techniques. Concretely, reported Flow methods applied to the determination or monitoring of inorganic analytes (viz. carbon, nitrogen, phosphorous and silicon species) together with some related compounds to assess water quality in drinking, rain, underground, marine, river, estuarine, waste and industrial samples are reviewed. For the first time, the most widespread Flow techniques of Analysis described in the literature (viz. Segmented Flow Analysis (SFA), continuous Flow Analysis (CFA), Flow injection Analysis (FIA), sequential injection Analysis (SIA), multicommuted FIA (MCFIA), multisyringe FIA (MSFIA), along with the different exploited injection modalities are included in the same review.

Alain Aminot - One of the best experts on this subject based on the ideXlab platform.

  • A re-examination of matrix effects in the Segmented-Flow Analysis of nutrients in sea and estuarine water.
    Analytica chimica acta, 2011
    Co-Authors: Stephen Coverly, Roger Kerouel, Alain Aminot
    Abstract:

    Modern instruments together with the use of standard reference materials have improved the accuracy and long-term reproducibility of the Analysis of nutrients (ammonium, nitrate, nitrite, phosphate and silicate) in sea water using Segmented-Flow Analysis, so that errors arising from matrix effects become more significant. Colorimetric detectors with bubble-through Flowcells have become widely used for seawater Analysis in recent years and their associated matrix effects are described. A re-examination of all categories of matrix effects, whose main origin is salinity, was thus undertaken to assess how much they are liable to alter the data. Interferences were classified into four types, each of which was examined in order to show its influence on the measurements. We discuss how matrix effects can be identified, quantified, reduced and corrected. Chemistry and instrument design play a major role in some matrix effects and recommendations are given to minimise these or make them easier to correct. In particular, the correction for chemical salt effects is revisited for the general case and new, simplified procedures are proposed for its computation. A semi-automated procedure is proposed for measuring and correcting sample and refractive index blanks.

  • Fluorometric determination of ammonia in sea and estuarine waters by direct Segmented Flow Analysis
    Marine Chemistry, 1997
    Co-Authors: Roger Kerouel, Alain Aminot
    Abstract:

    Abstract A direct automated method for routine determination of ammonia in sea and estuarine waters has been developed using Segmented Flow Analysis. The method, based on the reaction of ammonia with orthophtaldialdehyde (OPA) and sulfite, is easy to use, sensitive and highly reproducible. The combination of reagents makes it highly selective, thus eliminating the need for the gas diffusion cell commonly used to remove amino acid interference. Results on kinetics, on reagent composition and light effects and on pH and salinity changes are presented. The salt-effect does not exceed 3% in the 0–35 salinity range. Interference from primary amines is −1 ); specific recommendations are provided accordingly. Repeatability of 0.01 μmol l −1 was achieved in marine samples with ammonia concentrations ranging from 0.5 to 5 μmol l −1 . Using on-line dilution, ammonia determination can be performed up to 250 μmol l −1 and salt effect becomes negligible. Comparison of the present OPA-method with the indophenol blue method yielded fully comparable results.

Allen D. Budde - One of the best experts on this subject based on the ideXlab platform.

  • Wort Free Amino Nitrogen Analysis Adapted to a Microplate Format
    Cerevisia, 2013
    Co-Authors: Mark R. Schmitt, Allen D. Budde
    Abstract:

    J. Am. Soc. Brew. Chem. 70(2):95-102, 2012 The standard method for determining wort free amino nitrogen content is a long-established but now relatively outdated procedure, calling for the use of test tubes, marbles, several water baths (boiling and 20°C), manual sample transfers, and a conventional spectrophotometer. Currently, many malting quality laboratories avoid use of this cumbersome manual system by adopting automated chemistry Analysis systems as their in-house standard method for wort free amino nitrogen Analysis. Several recent papers have taken a somewhat different approach to measuring malting quality by adapting the basic analytical method to microtiter plates, microplate readers, and related instrumentation. This streamlines sample handling and increases sample capacity. However, results from the several free amino nitrogen methods published previously have not been directly compared. In this study, we analyzed several malts using the standard ASBC Wort-12 method, our standard Skalar Segmented Flow Analysis chemistry system, and several variations of those two chemistries in microplate formats to compare the results obtained by the different Analysis systems. Among these methods, the results from the manual ASBC Wort-12, the automated Skalar system, and a microplate-format assay based on the Skalar reagents agreed well. Surprisingly, however, direct adaptation of the Wort-12 reagents, times, and temperatures to the microplate format yielded inconsistent results. We examined a number of parameters in the microplate-format Wort-12 implementation but were unable to identify a single factor responsible for the divergence of results. From these results, we recommend adapting the chemistry from the Skalar Segmented Flow Analysis system to a microplate format for Analysis of wort free amino nitrogen content.

  • Wort Free Amino Nitrogen Analysis Adapted to a Microplate
    2012
    Co-Authors: Mark R. Schmitt, Allen D. Budde
    Abstract:

    J. Am. Soc. Brew. Chem. 70(2):95-102, 2012 The standard method for determining wort free amino nitrogen content is a long-established but now relatively outdated procedure, calling for the use of test tubes, marbles, several water baths (boiling and 20°C), manual sample transfers, and a conventional spectrophotometer. Currently, many malting quality laboratories avoid use of this cumbersome manual system by adopting automated chemistry Analysis systems as their in-house standard method for wort free amino nitrogen Analysis. Several recent papers have taken a somewhat different approach to measuring malting quality by adapting the basic analytical method to microtiter plates, microplate readers, and related instrumentation. This streamlines sample handling and increases sample capacity. However, results from the several free amino nitrogen methods published previously have not been directly compared. In this study, we analyzed several malts using the standard ASBC Wort-12 method, our standard Skalar Segmented Flow Analysis chemistry system, and several variations of those two chemistries in microplate formats to compare the results obtained by the different Analysis systems. Among these methods, the results from the manual ASBC Wort-12, the automated Skalar system, and a microplate-format assay based on the Skalar reagents agreed well. Surprisingly, however, direct adaptation of the Wort-12 reagents, times, and temperatures to the microplate format yielded inconsistent results. We examined a number of parameters in the microplate-format Wort-12 implementation but were unable to identify a single factor responsible for the divergence of results. From these results, we recommend adapting the chemistry from the Skalar Segmented Flow Analysis system to a microplate format for Analysis of wort free amino nitrogen content.

  • Calcofluor fluorescence assay for wort β-glucan in a microplate format.
    Cereal Chemistry Journal, 2009
    Co-Authors: Mark R. Schmitt, Allen D. Budde
    Abstract:

    The level of β-glucan in worts produced from malted barley is a critical malting quality parameter. Measurement of wort β-glucan levels allows maltsters to determine whether production malts meet commercial specifications, helps brewers avoid production problems due to slow lautering, and enables barley breeders to develop lines with the potential to meet commercial needs. Many laboratories performing routine wort β-glucan analyses use Flow injection Analysis (FIA) methods or related Segmented Flow Analysis (SFA) methods that measure the increase in fluorescence with Calcofluor binding to β-glucan. Such automated systems are attractive due to low per-sample reagent costs, relatively high sample throughput, and a minimal number of sample processing steps prior to automated Analysis, limiting the need for manual operations. However, FIA or SFA methodology requires significant capital investment for instrument acquisition, discouraging its use outside dedicated quality assurance laboratories. Laboratories that routinely analyze relatively few samples often find kits for enzymatic or colorimetric Analysis of β-glucans more attractive. Such kits require relatively simple laboratory instrumentation, reducing capital costs, but may involve multiple sample manipulations, increasing the level of technical support necessary to perform the analyses. Per-Analysis reagent costs may also be greater for the kits. In this work, we have adapted the Calcofluor fluorescence method to a microplate reader to achieve a simple and cost-effective assay for wort β-glucan that avoids the acquisition costs of FIA or SFA instrumentation.