ORALS

SESSION: ElectrochemistryWedPM1-R10	4th Intl. Symp. on Electrochemistry for Sustainable Development
Wed. 29 Nov. 2023 / Room: Boardroom
Session Chairs: Alexander Oleinick; Ali Seifitokaldani; Session Monitor: TBA

14:05: [ElectrochemistryWedPM105] OS Plenary
IMPORTANCE OF DIFFUSIONAL CONSTRAINTS IN QUANTITATIVE EVALUATION OF CALIBRATION CURVES OF ENZYMATIC MICRO- AND NANOELECTROCHEMICAL SENSORS
Reina Dannaoui¹ ; Xiao-Ke Yang² ; Wei-Hua Huang² ; Irina Svir³ ; Alexander Oleinick⁴ ; Christian Andre Amatore⁵ ; ¹CNRS, ENS - PSL University, Sorbonne University, Paris, France; ²Wuhan University, Wuhan, China; ³CNRS & PSL, Paris, France; ⁴CNRS, Paris, France; ⁵CNRS & PSL, French Academy of Sciences, Paris, France;
Paper Id: 174 [Abstract]

Electrochemical calibration curves recorded at enzyme-modified micro- or nanoelectrodes are often quantitatively analysed using graphical approaches directly inspired from the practice widely used in enzymatic analysis when enzymes as well as their substrate and cofactors are homogeneously distributed in the electrolytic solution [1-3]. We will introduce a concise and simple but highly representative model [4] that demonstrates that this practice yields incorrect interpretation of the experimental results even for simple Michaelis-Menten mechanisms. The present modelling makes it possible to establish the correct relationships linking calibration currents and bulk substrate concentrations by a simple method allowing to take into account the biases due to diffusional constraints when steady or quasi-steady state conditions are achieved as occurs experimentally during calibrations of micro- and nanoelectrochemical sensors.These correct relationships provide kinetic data characterizing a given sensor that ought to be considered whenever a calibrated enzymatic electrochemical sensor is aimed to be used under non-steady state condition, e.g., as for monitoring transient concentration releases of target analytes under in vivo or pseudo in vivo conditions.The authors would like to acknowledge support from joint sino-french CNRS IRP NanoBioCatEchem. CA thanks Xiamen University for his Distinguished Visiting Professor position.

References:
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[2] X.K. Yang, F.L Zhang, W.T. Wu, Y. Tang, J. Yan, Y.L. Liu, C. Amatore, W.H. Huang. Quantitative Nano-Amperometric Measurement of Intravesicular Glutamate Content and of its Sub-Quantal Release by Living Neurons. Angew. Chem. Int. Ed. 60 (2021) 15803-15808.
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[4] R. Dannaoui, X.-K. Yang, W.-H. Huang, I. Svir, C. Amatore, A. Oleinick, 2023, submitted.