@article{53433f94f43246daaf12b17900564f5d,
title = "Dynamic sensor concept combining electrochemical pH manipulation and optical sensing of buffer capacity",
abstract = "State-of-the-art electrochemical and optical sensors present distinct advantages and disadvantages when used individually. Combining both methodologies offers interesting synergies and makes it possible to exploit strengths and circumvent possible problems of the individual methods. We report a dynamic sensing concept for buffer capacity by applying water electrolysis to modulate the pH microenvironment in front of an optical pH sensor placed in a flow cell. Using this combinatory approach in a nonequilibrium readout mode allowed us to assess the concentration of different buffer species in relatively short time (1 min per measurement). Theoretical simulations of the system were performed to validate the presented method. Additionally, the dynamic measurement approach enabled in situ determination of the apparent pKa of MOPS (3-(N-morpholino)propanesulfonic acid) buffer at ambient conditions. The dynamic and combinatory approach presented here holds large potential also for other pH-active analytes.",
author = "Klaus Koren and Fabian Steininger and Zieger, {Silvia E.}",
note = "Funding Information: This study was supported by research grants from the Grundfos Foundation (K.K.) and a Sapere Aude grant from the Independent Research Fund Denmark (IRFD): DFF-804800057B (K.K.). An ERASMUS+ internship grant enabled F.S. to conduct this study at Aarhus University. The authors want to thank Lars Borregaard Pedersen, Mette L. G. Nikolajsen, and Ronny Mario Baaske for excellent technical support. Theresa Merl and Deby Fapyane are thanked for constructive discussions and support. The authors wish to state their gratitude to Anders Bentien (Aarhus University) for valuable discussions, Bernhard J. M?ller and the entire PyroScience team for help with the pH sensors, Hans R?y (Aarhus University) for help with the simulations, Niels Peter Revsbech (Aarhus University) for valuable feedback on the manuscript, and Sergey Borisov (Graz University of Technology, Austria) for constructive feedback and for supporting the mobility of F.S. Funding Information: This study was supported by research grants from the Grundfos Foundation (K.K.) and a Sapere Aude grant from the Independent Research Fund Denmark (IRFD): DFF-8048-00057B (K.K.). An ERASMUS+ internship grant enabled F.S. to conduct this study at Aarhus University. The authors want to thank Lars Borregaard Pedersen, Mette L. G. Nikolajsen, and Ronny Mario Baaske for excellent technical support. Theresa Merl and Deby Fapyane are thanked for constructive discussions and support. The authors wish to state their gratitude to Anders Bentien (Aarhus University) for valuable discussions, Bernhard J. M{\"u}ller and the entire PyroScience team for help with the pH sensors, Hans R{\o}y (Aarhus University) for help with the simulations, Niels Peter Revsbech (Aarhus University) for valuable feedback on the manuscript, and Sergey Borisov (Graz University of Technology, Austria) for constructive feedback and for supporting the mobility of F.S. Publisher Copyright: {\textcopyright} 2021 American Chemical Society",
year = "2021",
month = mar,
day = "2",
doi = "10.1021/acs.analchem.0c04326",
language = "English",
volume = "93",
pages = "3822--3829",
journal = "Analytical Chemistry",
issn = "0003-2700",
publisher = "American Chemical Society",
number = "8",
}