The Experts below are selected from a list of 80721 Experts worldwide ranked by ideXlab platform

Tatsuo Yoshinobu - One of the best experts on this subject based on the ideXlab platform.

  • application of Chemical Imaging sensor to in situ ph Imaging in the vicinity of a corroding metal surface
    Electrochimica Acta, 2015
    Co-Authors: Koichiro Miyamoto, Torsten Wagner, Michael J Schoning, Sakura Sakakita, Tatsuo Yoshinobu
    Abstract:

    Abstract The Chemical Imaging sensor was applied to in - situ pH Imaging of the solution in the vicinity of a corroding surface of stainless steel under potentiostatic polarization. A test piece of polished stainless steel was placed on the sensing surface leaving a narrow gap filled with artificial seawater and the stainless steel was corroded under polarization. The pH images obtained during polarization showed correspondence between the region of lower pH and the site of corrosion. It was also found that the pH value in the gap became as low as 2 by polarization, which triggered corrosion.

  • recent developments of Chemical Imaging sensor systems based on the principle of the light addressable potentiometric sensor
    Sensors and Actuators B-chemical, 2015
    Co-Authors: Tatsuo Yoshinobu, Koichiro Miyamoto, Torsten Wagner, Michael J Schoning
    Abstract:

    Abstract The light-addressable potentiometric sensor (LAPS) is an electroChemical sensor with a field-effect structure to detect the variation of the Nernst potential at its sensor surface, the measured area on which is defined by illumination. Thanks to this light-addressability, the LAPS can be applied to Chemical Imaging sensor systems, which can visualize the two-dimensional distribution of a particular target ion on the sensor surface. Chemical Imaging sensor systems are expected to be useful for analysis of reaction and diffusion in various electroChemical and biological samples. Recent developments of LAPS-based Chemical Imaging sensor systems, in terms of the spatial resolution, measurement speed, image quality, miniaturization and integration with microfluidic devices, are summarized and discussed.

  • high speed Chemical Imaging inside a microfluidic channel
    Sensors and Actuators B-chemical, 2014
    Co-Authors: Koichiro Miyamoto, Torsten Wagner, Michael J Schoning, Akinori Itabashi, Tatsuo Yoshinobu
    Abstract:

    Abstract In this study, a high-speed Chemical Imaging system was developed for visualization of the interior of a microfluidic channel. A microfluidic channel was constructed on the sensor surface of the light-addressable potentiometric sensor (LAPS), on which the ion concentrations could be measured in parallel at up to 64 points illuminated by optical fibers. The temporal change of pH distribution inside the microfluidic channel was recorded at a maximum rate of 100 frames per second (fps). The high frame rate allowed visualization of moving interfaces and plugs in the channel even at a flow velocity of 111 mm/s, which suggests the feasibility of plug-based microfluidic devices for flow-injection analysis (FIA).

  • Chemical Imaging of the concentration profile of ion diffusion in a microfluidic channel
    Sensors and Actuators B-chemical, 2013
    Co-Authors: Koichiro Miyamoto, Hiroki Ichimura, Torsten Wagner, Michael J Schoning, Tatsuo Yoshinobu
    Abstract:

    Abstract The Chemical Imaging sensor is a device to visualize the spatial distribution of Chemical species based on the principle of LAPS (light-addressable potentiometric sensor), which is a field-effect Chemical sensor based on semiconductor. In this study, the Chemical Imaging sensor has been applied to investigate the ion profile of laminar flows in a microfluidic channel. The Chemical images (pH maps) were collected in a Y-shaped microfluidic channel while injecting HCl and NaCl solutions into two branches. From the Chemical images, it was clearly observed that the injected solutions formed laminar flows in the channel. In addition, ion diffusion across the laminar flows was observed, and the diffusion coefficient could be derived by fitting the pH profiles to the Fick's equation.

  • development and characterisation of a compact light addressable potentiometric sensor laps based on the digital light processing dlp technology for flexible Chemical Imaging
    Sensors and Actuators B-chemical, 2012
    Co-Authors: Torsten Wagner, Koichiro Miyamoto, Michael J Schoning, Carl Frederik Werner, Tatsuo Yoshinobu
    Abstract:

    Abstract Chemical Imaging systems allow the visualisation of the distribution of Chemical species on the sensor surface. This work represents a new flexible approach to read out light-addressable potentiometric sensors (LAPS) with the help of a digital light processing (DLP) set-up. The DLP, known well for video projectors, consists of a mirror-array MEMS device, which allows fast and flexible generation of light patterns. With the help of these light patterns, the sensor surface of the LAPS device can be addressed. The DLP approach has several advantages compared to conventional LAPS set-ups, e.g., the spot size and the shape of the light pointer can be changed easily and no mechanical movement is necessary, which reduces the size of the set-up and increases the stability and speed of the measurement. In addition, the modulation frequency and intensity of the light beam are important parameters of the LAPS set-up. Within this work, the authors will discuss two different ways of light modulation by the DLP set-up, investigate the influence of different modulation frequencies and different light intensities as well as demonstrate the scanning capabilities of the new set-up by pH mapping on the sensor surface.

Michael J Schoning - One of the best experts on this subject based on the ideXlab platform.

  • application of Chemical Imaging sensor to in situ ph Imaging in the vicinity of a corroding metal surface
    Electrochimica Acta, 2015
    Co-Authors: Koichiro Miyamoto, Torsten Wagner, Michael J Schoning, Sakura Sakakita, Tatsuo Yoshinobu
    Abstract:

    Abstract The Chemical Imaging sensor was applied to in - situ pH Imaging of the solution in the vicinity of a corroding surface of stainless steel under potentiostatic polarization. A test piece of polished stainless steel was placed on the sensing surface leaving a narrow gap filled with artificial seawater and the stainless steel was corroded under polarization. The pH images obtained during polarization showed correspondence between the region of lower pH and the site of corrosion. It was also found that the pH value in the gap became as low as 2 by polarization, which triggered corrosion.

  • recent developments of Chemical Imaging sensor systems based on the principle of the light addressable potentiometric sensor
    Sensors and Actuators B-chemical, 2015
    Co-Authors: Tatsuo Yoshinobu, Koichiro Miyamoto, Torsten Wagner, Michael J Schoning
    Abstract:

    Abstract The light-addressable potentiometric sensor (LAPS) is an electroChemical sensor with a field-effect structure to detect the variation of the Nernst potential at its sensor surface, the measured area on which is defined by illumination. Thanks to this light-addressability, the LAPS can be applied to Chemical Imaging sensor systems, which can visualize the two-dimensional distribution of a particular target ion on the sensor surface. Chemical Imaging sensor systems are expected to be useful for analysis of reaction and diffusion in various electroChemical and biological samples. Recent developments of LAPS-based Chemical Imaging sensor systems, in terms of the spatial resolution, measurement speed, image quality, miniaturization and integration with microfluidic devices, are summarized and discussed.

  • high speed Chemical Imaging inside a microfluidic channel
    Sensors and Actuators B-chemical, 2014
    Co-Authors: Koichiro Miyamoto, Torsten Wagner, Michael J Schoning, Akinori Itabashi, Tatsuo Yoshinobu
    Abstract:

    Abstract In this study, a high-speed Chemical Imaging system was developed for visualization of the interior of a microfluidic channel. A microfluidic channel was constructed on the sensor surface of the light-addressable potentiometric sensor (LAPS), on which the ion concentrations could be measured in parallel at up to 64 points illuminated by optical fibers. The temporal change of pH distribution inside the microfluidic channel was recorded at a maximum rate of 100 frames per second (fps). The high frame rate allowed visualization of moving interfaces and plugs in the channel even at a flow velocity of 111 mm/s, which suggests the feasibility of plug-based microfluidic devices for flow-injection analysis (FIA).

  • Chemical Imaging of the concentration profile of ion diffusion in a microfluidic channel
    Sensors and Actuators B-chemical, 2013
    Co-Authors: Koichiro Miyamoto, Hiroki Ichimura, Torsten Wagner, Michael J Schoning, Tatsuo Yoshinobu
    Abstract:

    Abstract The Chemical Imaging sensor is a device to visualize the spatial distribution of Chemical species based on the principle of LAPS (light-addressable potentiometric sensor), which is a field-effect Chemical sensor based on semiconductor. In this study, the Chemical Imaging sensor has been applied to investigate the ion profile of laminar flows in a microfluidic channel. The Chemical images (pH maps) were collected in a Y-shaped microfluidic channel while injecting HCl and NaCl solutions into two branches. From the Chemical images, it was clearly observed that the injected solutions formed laminar flows in the channel. In addition, ion diffusion across the laminar flows was observed, and the diffusion coefficient could be derived by fitting the pH profiles to the Fick's equation.

  • development and characterisation of a compact light addressable potentiometric sensor laps based on the digital light processing dlp technology for flexible Chemical Imaging
    Sensors and Actuators B-chemical, 2012
    Co-Authors: Torsten Wagner, Koichiro Miyamoto, Michael J Schoning, Carl Frederik Werner, Tatsuo Yoshinobu
    Abstract:

    Abstract Chemical Imaging systems allow the visualisation of the distribution of Chemical species on the sensor surface. This work represents a new flexible approach to read out light-addressable potentiometric sensors (LAPS) with the help of a digital light processing (DLP) set-up. The DLP, known well for video projectors, consists of a mirror-array MEMS device, which allows fast and flexible generation of light patterns. With the help of these light patterns, the sensor surface of the LAPS device can be addressed. The DLP approach has several advantages compared to conventional LAPS set-ups, e.g., the spot size and the shape of the light pointer can be changed easily and no mechanical movement is necessary, which reduces the size of the set-up and increases the stability and speed of the measurement. In addition, the modulation frequency and intensity of the light beam are important parameters of the LAPS set-up. Within this work, the authors will discuss two different ways of light modulation by the DLP set-up, investigate the influence of different modulation frequencies and different light intensities as well as demonstrate the scanning capabilities of the new set-up by pH mapping on the sensor surface.

Koichiro Miyamoto - One of the best experts on this subject based on the ideXlab platform.

  • application of Chemical Imaging sensor to in situ ph Imaging in the vicinity of a corroding metal surface
    Electrochimica Acta, 2015
    Co-Authors: Koichiro Miyamoto, Torsten Wagner, Michael J Schoning, Sakura Sakakita, Tatsuo Yoshinobu
    Abstract:

    Abstract The Chemical Imaging sensor was applied to in - situ pH Imaging of the solution in the vicinity of a corroding surface of stainless steel under potentiostatic polarization. A test piece of polished stainless steel was placed on the sensing surface leaving a narrow gap filled with artificial seawater and the stainless steel was corroded under polarization. The pH images obtained during polarization showed correspondence between the region of lower pH and the site of corrosion. It was also found that the pH value in the gap became as low as 2 by polarization, which triggered corrosion.

  • recent developments of Chemical Imaging sensor systems based on the principle of the light addressable potentiometric sensor
    Sensors and Actuators B-chemical, 2015
    Co-Authors: Tatsuo Yoshinobu, Koichiro Miyamoto, Torsten Wagner, Michael J Schoning
    Abstract:

    Abstract The light-addressable potentiometric sensor (LAPS) is an electroChemical sensor with a field-effect structure to detect the variation of the Nernst potential at its sensor surface, the measured area on which is defined by illumination. Thanks to this light-addressability, the LAPS can be applied to Chemical Imaging sensor systems, which can visualize the two-dimensional distribution of a particular target ion on the sensor surface. Chemical Imaging sensor systems are expected to be useful for analysis of reaction and diffusion in various electroChemical and biological samples. Recent developments of LAPS-based Chemical Imaging sensor systems, in terms of the spatial resolution, measurement speed, image quality, miniaturization and integration with microfluidic devices, are summarized and discussed.

  • high speed Chemical Imaging inside a microfluidic channel
    Sensors and Actuators B-chemical, 2014
    Co-Authors: Koichiro Miyamoto, Torsten Wagner, Michael J Schoning, Akinori Itabashi, Tatsuo Yoshinobu
    Abstract:

    Abstract In this study, a high-speed Chemical Imaging system was developed for visualization of the interior of a microfluidic channel. A microfluidic channel was constructed on the sensor surface of the light-addressable potentiometric sensor (LAPS), on which the ion concentrations could be measured in parallel at up to 64 points illuminated by optical fibers. The temporal change of pH distribution inside the microfluidic channel was recorded at a maximum rate of 100 frames per second (fps). The high frame rate allowed visualization of moving interfaces and plugs in the channel even at a flow velocity of 111 mm/s, which suggests the feasibility of plug-based microfluidic devices for flow-injection analysis (FIA).

  • Chemical Imaging of the concentration profile of ion diffusion in a microfluidic channel
    Sensors and Actuators B-chemical, 2013
    Co-Authors: Koichiro Miyamoto, Hiroki Ichimura, Torsten Wagner, Michael J Schoning, Tatsuo Yoshinobu
    Abstract:

    Abstract The Chemical Imaging sensor is a device to visualize the spatial distribution of Chemical species based on the principle of LAPS (light-addressable potentiometric sensor), which is a field-effect Chemical sensor based on semiconductor. In this study, the Chemical Imaging sensor has been applied to investigate the ion profile of laminar flows in a microfluidic channel. The Chemical images (pH maps) were collected in a Y-shaped microfluidic channel while injecting HCl and NaCl solutions into two branches. From the Chemical images, it was clearly observed that the injected solutions formed laminar flows in the channel. In addition, ion diffusion across the laminar flows was observed, and the diffusion coefficient could be derived by fitting the pH profiles to the Fick's equation.

  • development and characterisation of a compact light addressable potentiometric sensor laps based on the digital light processing dlp technology for flexible Chemical Imaging
    Sensors and Actuators B-chemical, 2012
    Co-Authors: Torsten Wagner, Koichiro Miyamoto, Michael J Schoning, Carl Frederik Werner, Tatsuo Yoshinobu
    Abstract:

    Abstract Chemical Imaging systems allow the visualisation of the distribution of Chemical species on the sensor surface. This work represents a new flexible approach to read out light-addressable potentiometric sensors (LAPS) with the help of a digital light processing (DLP) set-up. The DLP, known well for video projectors, consists of a mirror-array MEMS device, which allows fast and flexible generation of light patterns. With the help of these light patterns, the sensor surface of the LAPS device can be addressed. The DLP approach has several advantages compared to conventional LAPS set-ups, e.g., the spot size and the shape of the light pointer can be changed easily and no mechanical movement is necessary, which reduces the size of the set-up and increases the stability and speed of the measurement. In addition, the modulation frequency and intensity of the light beam are important parameters of the LAPS set-up. Within this work, the authors will discuss two different ways of light modulation by the DLP set-up, investigate the influence of different modulation frequencies and different light intensities as well as demonstrate the scanning capabilities of the new set-up by pH mapping on the sensor surface.

Torsten Wagner - One of the best experts on this subject based on the ideXlab platform.

  • application of Chemical Imaging sensor to in situ ph Imaging in the vicinity of a corroding metal surface
    Electrochimica Acta, 2015
    Co-Authors: Koichiro Miyamoto, Torsten Wagner, Michael J Schoning, Sakura Sakakita, Tatsuo Yoshinobu
    Abstract:

    Abstract The Chemical Imaging sensor was applied to in - situ pH Imaging of the solution in the vicinity of a corroding surface of stainless steel under potentiostatic polarization. A test piece of polished stainless steel was placed on the sensing surface leaving a narrow gap filled with artificial seawater and the stainless steel was corroded under polarization. The pH images obtained during polarization showed correspondence between the region of lower pH and the site of corrosion. It was also found that the pH value in the gap became as low as 2 by polarization, which triggered corrosion.

  • recent developments of Chemical Imaging sensor systems based on the principle of the light addressable potentiometric sensor
    Sensors and Actuators B-chemical, 2015
    Co-Authors: Tatsuo Yoshinobu, Koichiro Miyamoto, Torsten Wagner, Michael J Schoning
    Abstract:

    Abstract The light-addressable potentiometric sensor (LAPS) is an electroChemical sensor with a field-effect structure to detect the variation of the Nernst potential at its sensor surface, the measured area on which is defined by illumination. Thanks to this light-addressability, the LAPS can be applied to Chemical Imaging sensor systems, which can visualize the two-dimensional distribution of a particular target ion on the sensor surface. Chemical Imaging sensor systems are expected to be useful for analysis of reaction and diffusion in various electroChemical and biological samples. Recent developments of LAPS-based Chemical Imaging sensor systems, in terms of the spatial resolution, measurement speed, image quality, miniaturization and integration with microfluidic devices, are summarized and discussed.

  • high speed Chemical Imaging inside a microfluidic channel
    Sensors and Actuators B-chemical, 2014
    Co-Authors: Koichiro Miyamoto, Torsten Wagner, Michael J Schoning, Akinori Itabashi, Tatsuo Yoshinobu
    Abstract:

    Abstract In this study, a high-speed Chemical Imaging system was developed for visualization of the interior of a microfluidic channel. A microfluidic channel was constructed on the sensor surface of the light-addressable potentiometric sensor (LAPS), on which the ion concentrations could be measured in parallel at up to 64 points illuminated by optical fibers. The temporal change of pH distribution inside the microfluidic channel was recorded at a maximum rate of 100 frames per second (fps). The high frame rate allowed visualization of moving interfaces and plugs in the channel even at a flow velocity of 111 mm/s, which suggests the feasibility of plug-based microfluidic devices for flow-injection analysis (FIA).

  • Chemical Imaging of the concentration profile of ion diffusion in a microfluidic channel
    Sensors and Actuators B-chemical, 2013
    Co-Authors: Koichiro Miyamoto, Hiroki Ichimura, Torsten Wagner, Michael J Schoning, Tatsuo Yoshinobu
    Abstract:

    Abstract The Chemical Imaging sensor is a device to visualize the spatial distribution of Chemical species based on the principle of LAPS (light-addressable potentiometric sensor), which is a field-effect Chemical sensor based on semiconductor. In this study, the Chemical Imaging sensor has been applied to investigate the ion profile of laminar flows in a microfluidic channel. The Chemical images (pH maps) were collected in a Y-shaped microfluidic channel while injecting HCl and NaCl solutions into two branches. From the Chemical images, it was clearly observed that the injected solutions formed laminar flows in the channel. In addition, ion diffusion across the laminar flows was observed, and the diffusion coefficient could be derived by fitting the pH profiles to the Fick's equation.

  • development and characterisation of a compact light addressable potentiometric sensor laps based on the digital light processing dlp technology for flexible Chemical Imaging
    Sensors and Actuators B-chemical, 2012
    Co-Authors: Torsten Wagner, Koichiro Miyamoto, Michael J Schoning, Carl Frederik Werner, Tatsuo Yoshinobu
    Abstract:

    Abstract Chemical Imaging systems allow the visualisation of the distribution of Chemical species on the sensor surface. This work represents a new flexible approach to read out light-addressable potentiometric sensors (LAPS) with the help of a digital light processing (DLP) set-up. The DLP, known well for video projectors, consists of a mirror-array MEMS device, which allows fast and flexible generation of light patterns. With the help of these light patterns, the sensor surface of the LAPS device can be addressed. The DLP approach has several advantages compared to conventional LAPS set-ups, e.g., the spot size and the shape of the light pointer can be changed easily and no mechanical movement is necessary, which reduces the size of the set-up and increases the stability and speed of the measurement. In addition, the modulation frequency and intensity of the light beam are important parameters of the LAPS set-up. Within this work, the authors will discuss two different ways of light modulation by the DLP set-up, investigate the influence of different modulation frequencies and different light intensities as well as demonstrate the scanning capabilities of the new set-up by pH mapping on the sensor surface.

Ziemons Eric - One of the best experts on this subject based on the ideXlab platform.

  • Detection of low dose of piroxicam polymorph in pharmaceutical tablets by surface-enhanced Raman Chemical Imaging (SER-CI) and multivariate analysis
    'Elsevier BV', 2020
    Co-Authors: Cailletaud Johan, Ginot Yves-michel, Gut Yoann, Dumont Elodie, Hubert Philippe, De Bleye Charlotte, Sacre Pierre-yves, Leblanc Nicolas, Letellier Philippe, Ziemons Eric
    Abstract:

    peer reviewedaudience: researcher, professional, studentThis study demonstrates, for the first time, the ability of surface-enhanced Raman Chemical Imaging (SER-CI) combined with multivariate analysis to detect low levels (0.1% (w/w)) of a polymorphic form in a pharmaceutical mixture. In the studied formulation, piroxicam was used as a model molecule to develop this approach. Piroxicam is a widely available non-steroidal anti-inflammatory drug, exhibiting an interesting case of polymorphism, with two most commonly observed forms (β and α2). In this work, the SERS spectra of piroxicam polymorphic forms β and α2 are presented. These forms showed clear spectral differences in terms of band position and intensity. From a crystallographic point of view, the difference of exaltation between both forms was correlated with a preferred orientation of crystallites of form α2 making its SERS detection difficult compared to form β. A preferred orientation of the (1k0) crystallographic planes of α2 was demonstrated in samples, not promoting an appropriate molecular orientation onto the metallic surface. Additionally, a semi-quantitative approach using SER-CI combined with chemometric tools was developed enabling to detect crystallites of form β below the detection limit of conventional Raman microscopy. The exaltation of the Raman signal in the presence of silver nanoparticles allowed a higher sensitivity and a reduction of the acquisition time by a factor of 6

  • Detection of low dose of piroxicam polymorph in pharmaceutical tablets by surface-enhanced Raman Chemical Imaging (SER-CI) and multivariate analysis
    2020
    Co-Authors: Cailletaud Johan, Ginot Yves-michel, Gut Yoann, Dumont Elodie, Hubert Philippe, De Bleye Charlotte, Sacre Pierre-yves, Leblanc Nicolas, Letellier Philippe, Ziemons Eric
    Abstract:

    This study demonstrates, for the first time, the ability of surface-enhanced Raman Chemical Imaging (SER-CI) combined with multivariate analysis to detect low levels (0.1% (w/w)) of a polymorphic form in a pharmaceutical mixture. In the studied formulation, piroxicam was used as a model molecule to develop this approach. Piroxicam is a widely available non-steroidal anti-inflammatory drug, exhibiting an interesting case of polymorphism, with two most commonly observed forms (β and α2). In this work, the SERS spectra of piroxicam polymorphic forms β and α2 are presented. These forms showed clear spectral differences in terms of band position and intensity. From a crystallographic point of view, the difference of exaltation between both forms was correlated with a preferred orientation of crystallites of form α2 making its SERS detection difficult compared to form β. A preferred orientation of the (1k0) crystallographic planes of α2 was demonstrated in samples, not promoting an appropriate molecular orientation onto the metallic surface. Additionally, a semi-quantitative approach using SER-CI combined with chemometric tools was developed enabling to detect crystallites of form β below the detection limit of conventional Raman microscopy. The exaltation of the Raman signal in the presence of silver nanoparticles allowed a higher sensitivity and a reduction of the acquisition time by a factor of 6.Peer reviewe

  • Chemical Imaging: An essential mechanism to assess pharmaceutical (Part 1)
    Éditions de Santé, 2019
    Co-Authors: Bonnier Franck, Chauchard Fabien, Ginot Yves-michel, Gut Yoann, Michelet Alexandre, Tfayli Ali, Ziemons Eric
    Abstract:

    audience: researcher, professional, studentThis article is intended to make known the contribution of Chemical Imaging to the professions of pharmacy, biopharmacy or cosmetics, whether in the research phase of an active substance (experimental pharmacology), in the development of a formulation or in quality control, or even as an additional tool for solving quality-related problems in industrial production. It has been written for an uninitiated audience to provide the latter with the methodological basics and key points that will help it better understand the concept. Chemical Imaging is currently the only tool that allows us to visualise, without labelling, the spatial distribution of Chemical (or bioChemical) species within a sample. This is an essential added value compared to optical microscopy.his article is intended to make known the contribution of Chemical Imaging to the professions of pharmacy, biopharmacy or cosmetics, whether in the research phase of an active substance (experimental pharmacology), in the development of a formulation or in quality control, or even as an additional tool for solving quality-related problems in industrial production. It has been written for an uninitiated audience to provide the latter with the methodological basics and key points that will help it better understand the concept. Chemical Imaging is currently the only tool that allows us to visualise, without labelling, the spatial distribution of Chemical (or bioChemical) species within a sample. This is an essential added value compared to optical microscopy

  • Towards a spray-coating method for the detection of low-dose compounds in pharmaceutical tablets using surface-enhanced Raman Chemical Imaging (SER-CI)
    2018
    Co-Authors: Cailletaud Johan, Ginot Yves-michel, Gut Yoann, Dumont Elodie, Hubert Philippe, De Bleye Charlotte, Sacre Pierre-yves, Bultel Laurent, Ziemons Eric
    Abstract:

    Surface-enhanced Raman Chemical Imaging (SER-CI) is a highly sensitive analytical tool recently used in the pharmaceutical field owing to the possibility to obtain high sensitivity along with spatial information. However, the covering method of the pharmaceutical samples such as tablets with metallic nanoparticles is a major issue for SER-CI analyses due to the difficulty to obtain a homogeneous covering of tablet surface with the SERS substrates. In this context, a spray-coating method was proposed in order to fully exploit the potential of SER-CI. A homemade apparatus has been developed from an electrospray ionization (ESI) probe in order to cover the pharmaceutical tablets with the colloidal suspension in a homogeneous way. The silver substrate was pulled through the airbrush by a syringe pump which was then nebulized into small droplets due to the contact of the solution with the gas flow turbulence. A robust optimization of the process was carried out by adjusting experimental parameters such as the liquid flow rate and the spraying time. Besides, the performances of this spraying technique were compared with two others covering methods found in the literature which are drop casting and absorption coating. A homogeneity study, conducted by SER-CI and matrix assisted laser desorption/ ionization mass spectrometry Imaging (MALDI-MSI) applied to the different covering techniques was performed. The influence of the metallic nanoparticles deposit on soluble compounds was also investigated in order to highlight the advantages of using this new spray coating approach.Peer reviewe

  • Towards a spray-coating method for the detection of low-dose compounds in pharmaceutical tablets using surface-enhanced Raman Chemical Imaging (SER-CI)
    'Elsevier BV', 2018
    Co-Authors: Cailletaud Johan, Ginot Yves-michel, Gut Yoann, Dumont Elodie, Hubert Philippe, De Bleye Charlotte, Sacre Pierre-yves, Bultel Laurent, Ziemons Eric
    Abstract:

    peer reviewedaudience: researcher, professional, studentSurface-enhanced Raman Chemical Imaging (SER-CI) is a highly sensitive analytical tool recently used in the pharmaceutical field owing to the possibility to obtain high sensitivity along with spatial information. However, the covering method of the pharmaceutical samples such as tablets with metallic nanoparticles is a major issue for SER-CI analyses due to the difficulty to obtain a homogeneous covering of tablet surface with the SERS substrates. In this context, a spray-coating method was proposed in order to fully exploit the potential of SER-CI. A homemade apparatus has been developed from an electrospray ionization (ESI) probe in order to cover the pharmaceutical tablets with the colloidal suspension in a homogeneous way. The silver substrate was pulled through the airbrush by a syringe pump which was then nebulized into small droplets due to the contact of the solution with the gas flow turbulence. A robust optimization of the process was carried out by adjusting experimental parameters such as the liquid flow rate and the spraying time. Besides, the performances of this spraying technique were compared with two others covering methods found in the literature which are drop casting and absorption coating. A homogeneity study, conducted by SER-CI and matrix assisted laser desorption/ ionization mass spectrometry Imaging (MALDI-MSI) applied to the different covering techniques was performed. The influence of the metallic nanoparticles deposit on soluble compounds was also investigated in order to highlight the advantages of using this new spray coating approach