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Wei Qin - One of the best experts on this subject based on the ideXlab platform.

  • An integrated all-solid-state screen-printed Potentiometric Sensor based on a three-dimensional self-assembled graphene aerogel
    Microchemical Journal, 2020
    Co-Authors: Wei Qin
    Abstract:

    Abstract An integrated all-solid-state screen-printed ion-selective Potentiometric Sensor for the determination of Cu2+ is proposed. The whole-cell Potentiometric Sensor incorporates a polymeric membrane copper ion-selective electrode (Cu2+-ISE) as an indicator electrode and an Ag/AgCl reference electrode with a polyvinyl butyral reference membrane. The three-dimensional (3D) self-assembled porous graphene aerogel (PGA) can be conveniently and rapidly electrodeposited on the electrode substrate surface. Due to its interior 3D interconnected porous structures, the PGA has a large electrical double layer capacitance and fast charge transfer capability, which make it promising to be used as solid contact for the fabrication of the Cu2+-ISE. The developed Potentiometric Sensor shows a good Nernstian response over a range from 10−6 to 10−3 M with a detection limit of 10−6.5 M. In addition, the Sensor exhibits a stable potential response with the absence of an undesirable water layer at the ion-selective membrane/PGA interface.

  • imprinted nanobead based disposable screen printed Potentiometric Sensor for highly sensitive detection of 2 naphthoic acid
    Materials Letters, 2018
    Co-Authors: Rongning Liang, Xiaofeng Yang, Wei Qin, Rongning Liang, Wei Qin
    Abstract:

    Abstract Currently, Potentiometric Sensors based on various molecularly imprinted polymer (MIP) receptors have been successfully fabricated for detection of organic species. However, almost all of the previously developed Potentiometric Sensors based on MIPs are in traditional liquid-contact mode in which lower detection limits have been restricted by zero-current transmembrane ion fluxes. Herein, a screen-printed Potentiometric Sensor for determination of 2-naphthoic acid has been developed. It is based on the MIP nanobeads as the selective receptor and the electrochemically reduced graphene oxide film as the solid contact. Compared with the classical Potentiometric Sensor, the proposed Sensor based on nonequilibrium sensing mechanism exhibits remarkably improved detection sensitivity for 2-naphthoic acid with a low detection limit of 6.9 × 10−11 M.

  • Soluble Molecularly Imprinted Polymer-Based Potentiometric Sensor for Determination of Bisphenol AF
    Analytical chemistry, 2017
    Co-Authors: Huan Zhang, Ruiqing Yao, Ning Wang, Rongning Liang, Wei Qin, Rongning Liang, Wei Qin
    Abstract:

    Molecularly imprinted polymer (MIP)-based polymeric membrane Potentiometric Sensors have been successfully developed for determination of organic compounds in their ionic and neutral forms. However, most of the MIP receptors in Potentiometric Sensors developed so far are insoluble and cannot be well dissolved in the polymeric membranes. The heterogeneous molecular recognitions between the analytes and MIPs in the membranes are inefficient due to the less available binding sites of the MIPs. Herein we describe a novel polymeric membrane Potentiometric Sensor using a soluble MIP (s-MIP) as a receptor. The s-MIP is synthesized by the swelling of the traditional MIP at a high temperature. The obtained MIP can be dissolved in the plasticized polymeric membrane for homogeneous binding of the imprinted polymer to the target molecules. By using neutral bisphenol AF as a model, the proposed method exhibits an improved sensitivity compared to the conventional MIP-based Sensor with a lower detection limit of 60 nM. ...

  • Soluble Molecularly Imprinted Polymer-Based Potentiometric Sensor for Determination of Bisphenol AF
    2017
    Co-Authors: Huan Zhang, Ruiqing Yao, Ning Wang, Rongning Liang, Wei Qin, Rongning Liang, Wei Qin
    Abstract:

    Molecularly imprinted polymer (MIP)-based polymeric membrane Potentiometric Sensors have been successfully developed for determination of organic compounds in their ionic and neutral forms. However, most of the MIP receptors in Potentiometric Sensors developed so far are insoluble and cannot be well dissolved in the polymeric membranes. The heterogeneous molecular recognitions between the analytes and MIPs in the membranes are inefficient due to the less available binding sites of the MIPs. Herein we describe a novel polymeric membrane Potentiometric Sensor using a soluble MIP (s-MIP) as a receptor. The s-MIP is synthesized by the swelling of the traditional MIP at a high temperature. The obtained MIP can be dissolved in the plasticized polymeric membrane for homogeneous binding of the imprinted polymer to the target molecules. By using neutral bisphenol AF as a model, the proposed method exhibits an improved sensitivity compared to the conventional MIP-based Sensor with a lower detection limit of 60 nM. Moreover, the present Sensor exhibits an excellent selectivity over other phenols. We believe that s-MIPs can provide an appealing substitute for the traditional insoluble MIP receptors in the development of polymeric membrane-based electrochemical and optical Sensors

  • An all-solid-state imprinted polymer-based Potentiometric Sensor for determination of bisphenol S
    RSC Advances, 2016
    Co-Authors: Tiantian Wang, Ruiqing Yao, Rongning Liang, Tanji Yin, Wei Qin
    Abstract:

    An all-solid-state polymeric membrane Potentiometric Sensor for determination of bisphenol S has been developed by using the imprinted polymer as the receptor and a nanoporous gold film as the solid contact. The Sensor has a linear concentration range of 0.1 to 2 μM with a detection limit of 0.04 μM.

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

  • An on-chip electroosmotic micropump with a light- addressable Potentiometric Sensor
    Optoelectronics Letters, 2017
    Co-Authors: Shibin Liu, Ping-ping Fan, Carl Frederik Werner, Ko-ichiro Miyamoto, Tatsuo Yoshinobu
    Abstract:

    An on-chip electroosmotic (EO) micropump (EOP) was integrated in a microfluidic channel combined with a light-addressable Potentiometric Sensor (LAPS). The movement of EO flow towards right and left directions can be clearly observed in the microfluidic channel. The characteristics of photocurrent-time and photocurrent-bias voltage are obtained when buffer solution passes through the sensing region. The results demonstrate that the combination of an on-chip EOP with an LAPS is feasible.

  • 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, Ko-ichiro Miyamoto, Torsten Wagner, Michael J. Schöning
    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.

  • novel photoexcitation method for light addressable Potentiometric Sensor with higher spatial resolution
    Applied Physics Express, 2014
    Co-Authors: Yuanyuan Guo, Michael J. Schöning, Ko-ichiro Miyamoto, Torsten Wagner, Kosuke Seki, Tatsuo Yoshinobu
    Abstract:

    A novel photoexcitation method for the light-addressable Potentiometric Sensor (LAPS) is proposed to achieve a higher spatial resolution of chemical images. The proposed method employs a combined light source that consists of a modulated light probe, which generates the alternating photocurrent signal, and a ring of constant illumination surrounding it. The constant illumination generates a sheath of carriers with increased concentration which suppresses the spread of photocarriers by enhanced recombination. A device simulation was carried out to verify the effect of constant illumination on the spatial resolution, which demonstrated that a higher spatial resolution can be obtained.

  • device simulation of the light addressable Potentiometric Sensor with a novel photoexcitation method for a higher spatial resolution
    Procedia Engineering, 2014
    Co-Authors: Yuanyuan Guo, Michael J. Schöning, Ko-ichiro Miyamoto, Torsten Wagner, Kosuke Seki, Tatsuo Yoshinobu
    Abstract:

    Abstract A novel photoexcitation method for the light-addressable Potentiometric Sensor (LAPS) realized a higher spatial resolution of chemical imaging. In this method, a modulated light probe, which generates the alternating photocurrent signal, is surrounded by a ring of constant light, which suppresses the lateral diffusion of photocarriers by enhancing recombination. A device simulation verified that a higher spatial resolution could be obtained by adjusting the gap between the modulated and constant light. It was also found that a higher intensity and a longer wavelength of constant light was more effective. However, there exists a tradeoff between the spatial resolution and the amplitude of the photocurrent, and thus, the signal-to-noise ratio. A tilted incidence of constant light was applied, which could achieve even higher resolution with a smaller loss of photocurrent.

  • constant phase mode operation of the light addressable Potentiometric Sensor
    Procedia Chemistry, 2009
    Co-Authors: Ko-ichiro Miyamoto, Tatsuo Yoshinobu, Torsten Wagner, Shuhei Mimura, Shinichiro Kanoh, Michael J. Schöning
    Abstract:

    Abstract The constant-phase-mode operation of the light-addressable Potentiometric Sensor (LAPS) is proposed and demonstrated. In this new operation mode, the temporal change and the spatial distribution of the analyte concentration are recorded in the form of the bias voltage applied to the LAPS Sensor plate, which is servo-controlled to maintain the phase of the photocurrent at a constant value with respect to the light modulation. The constant-phase-mode LAPS is advantageous for its wider measurement range and reduction of artifacts.

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

  • 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, Ko-ichiro Miyamoto, Torsten Wagner, Michael J. Schöning
    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.

  • novel photoexcitation method for light addressable Potentiometric Sensor with higher spatial resolution
    Applied Physics Express, 2014
    Co-Authors: Yuanyuan Guo, Michael J. Schöning, Ko-ichiro Miyamoto, Torsten Wagner, Kosuke Seki, Tatsuo Yoshinobu
    Abstract:

    A novel photoexcitation method for the light-addressable Potentiometric Sensor (LAPS) is proposed to achieve a higher spatial resolution of chemical images. The proposed method employs a combined light source that consists of a modulated light probe, which generates the alternating photocurrent signal, and a ring of constant illumination surrounding it. The constant illumination generates a sheath of carriers with increased concentration which suppresses the spread of photocarriers by enhanced recombination. A device simulation was carried out to verify the effect of constant illumination on the spatial resolution, which demonstrated that a higher spatial resolution can be obtained.

  • device simulation of the light addressable Potentiometric Sensor with a novel photoexcitation method for a higher spatial resolution
    Procedia Engineering, 2014
    Co-Authors: Yuanyuan Guo, Michael J. Schöning, Ko-ichiro Miyamoto, Torsten Wagner, Kosuke Seki, Tatsuo Yoshinobu
    Abstract:

    Abstract A novel photoexcitation method for the light-addressable Potentiometric Sensor (LAPS) realized a higher spatial resolution of chemical imaging. In this method, a modulated light probe, which generates the alternating photocurrent signal, is surrounded by a ring of constant light, which suppresses the lateral diffusion of photocarriers by enhancing recombination. A device simulation verified that a higher spatial resolution could be obtained by adjusting the gap between the modulated and constant light. It was also found that a higher intensity and a longer wavelength of constant light was more effective. However, there exists a tradeoff between the spatial resolution and the amplitude of the photocurrent, and thus, the signal-to-noise ratio. A tilted incidence of constant light was applied, which could achieve even higher resolution with a smaller loss of photocurrent.

  • constant phase mode operation of the light addressable Potentiometric Sensor
    Procedia Chemistry, 2009
    Co-Authors: Ko-ichiro Miyamoto, Tatsuo Yoshinobu, Torsten Wagner, Shuhei Mimura, Shinichiro Kanoh, Michael J. Schöning
    Abstract:

    Abstract The constant-phase-mode operation of the light-addressable Potentiometric Sensor (LAPS) is proposed and demonstrated. In this new operation mode, the temporal change and the spatial distribution of the analyte concentration are recorded in the form of the bias voltage applied to the LAPS Sensor plate, which is servo-controlled to maintain the phase of the photocurrent at a constant value with respect to the light modulation. The constant-phase-mode LAPS is advantageous for its wider measurement range and reduction of artifacts.

  • Constant-phase-mode operation of the light-addressable Potentiometric Sensor
    Procedia Chemistry, 2009
    Co-Authors: Ko-ichiro Miyamoto, Tatsuo Yoshinobu, Torsten Wagner, Shuhei Mimura, Shinichiro Kanoh, Michael J. Schöning
    Abstract:

    AbstractWe herein propose and demonstrate the constant-phase-mode operation of the light-addressable Potentiometric Sensor (LAPS). The bias voltage applied to the LAPS Sensor plate is servo-controlled to maintain the phase of the photocurrent with respect to the light modulation at a constant value. In this new operation mode, the temporal change and the spatial distribution of the potential at the sensing surface can be recorded and converted into the analyte concentration. This LAPS with a constant-phasemode is advantageous due to its wider measurement range and reduction of artifacts

Li Niu - One of the best experts on this subject based on the ideXlab platform.

  • a multichannel electrochemical all solid state wearable Potentiometric Sensor for real time sweat ion monitoring
    Electrochemistry Communications, 2019
    Co-Authors: Shiyu Gan, Yu Bao, Huijun Kong, Lijie Zhong, Zhongqian Song, Li Niu
    Abstract:

    Abstract There is considerable interest in wearable Potentiometric ion Sensors that can provide information about the quality of a person's health by monitoring ion concentration levels in biofluids. Significant progress has been achieved, particularly in device integration. However, the crucial interfacial water layer and the use of transducer materials remain challenging. Herein we report a paper-based, flexible, all-solid-state, ion-selective electrode (ISE) for the real-time analysis of sweat. The super-hydrophobic paper matrix was modified with a fluorinated alkyl silane to reduce the water-layer effect. We used a high-quality graphene suspension with high conductivity and capacitance as an ion-to-electron transducer, which further stabilized the potential. The integrated solid ISE has four channels that can detect K+, Na+, Cl− and pH simultaneously. This wearable Potentiometric Sensor has reliable accuracy, good potential stability and low detection limits, and could be used in healthcare and clinical analysis.

Rongning Liang - One of the best experts on this subject based on the ideXlab platform.

  • a molecularly imprinted polymer based Potentiometric Sensor based on covalent recognition for the determination of dopamine
    Analytical Methods, 2021
    Co-Authors: Chan Wang, Rongning Liang
    Abstract:

    Polymeric membrane Potentiometric Sensors based on molecularly imprinted polymers (MIPs) have been successfully designed for the detection of organic compounds both in ionic and neutral forms. However, most of these Sensors are based on the non-covalent recognition interactions between the functional groups of the MIP in the polymeric sensing membrane and the target. These weak non-covalent interactions are unfavorable for the detection of hydrophilic organic compounds (e.g., dopamine). Herein novel MIP Potentiometric Sensor based covalent recognition for the determination of protonated dopamine is described. Uniform-sized boronate-based MIP beads are utilized as the recognition receptors. These receptors can covalently bind with dopamine with a cis-diol group to form a five-membered cyclic ester and thus provide a higher affinity because of the stronger nature of the covalent bonds. It has been found that the proposed electrode shows an excellent sensitivity towards dopamine with a detection limit of 2.1 μM, which could satisfy the needs for in vivo analysis of dopamine in the brain of living animals. We believe that the covalent recognition MIP-based sensing strategy provides an appealing way to design MIP-based electrochemical and optical Sensors with excellent sensing properties.

  • imprinted nanobead based disposable screen printed Potentiometric Sensor for highly sensitive detection of 2 naphthoic acid
    Materials Letters, 2018
    Co-Authors: Rongning Liang, Xiaofeng Yang, Wei Qin, Rongning Liang, Wei Qin
    Abstract:

    Abstract Currently, Potentiometric Sensors based on various molecularly imprinted polymer (MIP) receptors have been successfully fabricated for detection of organic species. However, almost all of the previously developed Potentiometric Sensors based on MIPs are in traditional liquid-contact mode in which lower detection limits have been restricted by zero-current transmembrane ion fluxes. Herein, a screen-printed Potentiometric Sensor for determination of 2-naphthoic acid has been developed. It is based on the MIP nanobeads as the selective receptor and the electrochemically reduced graphene oxide film as the solid contact. Compared with the classical Potentiometric Sensor, the proposed Sensor based on nonequilibrium sensing mechanism exhibits remarkably improved detection sensitivity for 2-naphthoic acid with a low detection limit of 6.9 × 10−11 M.

  • Soluble Molecularly Imprinted Polymer-Based Potentiometric Sensor for Determination of Bisphenol AF
    Analytical chemistry, 2017
    Co-Authors: Huan Zhang, Ruiqing Yao, Ning Wang, Rongning Liang, Wei Qin, Rongning Liang, Wei Qin
    Abstract:

    Molecularly imprinted polymer (MIP)-based polymeric membrane Potentiometric Sensors have been successfully developed for determination of organic compounds in their ionic and neutral forms. However, most of the MIP receptors in Potentiometric Sensors developed so far are insoluble and cannot be well dissolved in the polymeric membranes. The heterogeneous molecular recognitions between the analytes and MIPs in the membranes are inefficient due to the less available binding sites of the MIPs. Herein we describe a novel polymeric membrane Potentiometric Sensor using a soluble MIP (s-MIP) as a receptor. The s-MIP is synthesized by the swelling of the traditional MIP at a high temperature. The obtained MIP can be dissolved in the plasticized polymeric membrane for homogeneous binding of the imprinted polymer to the target molecules. By using neutral bisphenol AF as a model, the proposed method exhibits an improved sensitivity compared to the conventional MIP-based Sensor with a lower detection limit of 60 nM. ...

  • Soluble Molecularly Imprinted Polymer-Based Potentiometric Sensor for Determination of Bisphenol AF
    2017
    Co-Authors: Huan Zhang, Ruiqing Yao, Ning Wang, Rongning Liang, Wei Qin, Rongning Liang, Wei Qin
    Abstract:

    Molecularly imprinted polymer (MIP)-based polymeric membrane Potentiometric Sensors have been successfully developed for determination of organic compounds in their ionic and neutral forms. However, most of the MIP receptors in Potentiometric Sensors developed so far are insoluble and cannot be well dissolved in the polymeric membranes. The heterogeneous molecular recognitions between the analytes and MIPs in the membranes are inefficient due to the less available binding sites of the MIPs. Herein we describe a novel polymeric membrane Potentiometric Sensor using a soluble MIP (s-MIP) as a receptor. The s-MIP is synthesized by the swelling of the traditional MIP at a high temperature. The obtained MIP can be dissolved in the plasticized polymeric membrane for homogeneous binding of the imprinted polymer to the target molecules. By using neutral bisphenol AF as a model, the proposed method exhibits an improved sensitivity compared to the conventional MIP-based Sensor with a lower detection limit of 60 nM. Moreover, the present Sensor exhibits an excellent selectivity over other phenols. We believe that s-MIPs can provide an appealing substitute for the traditional insoluble MIP receptors in the development of polymeric membrane-based electrochemical and optical Sensors

  • An all-solid-state imprinted polymer-based Potentiometric Sensor for determination of bisphenol S
    RSC Advances, 2016
    Co-Authors: Tiantian Wang, Ruiqing Yao, Rongning Liang, Tanji Yin, Wei Qin
    Abstract:

    An all-solid-state polymeric membrane Potentiometric Sensor for determination of bisphenol S has been developed by using the imprinted polymer as the receptor and a nanoporous gold film as the solid contact. The Sensor has a linear concentration range of 0.1 to 2 μM with a detection limit of 0.04 μM.