ANEXO I This readme.txt file was generated on 2023-05-25 by Alvaro Colina Santamaría GENERAL INFORMATION 1. TITLE OF DATASET: Dataset of the work “Normal or parallel configuration in spectroelectrochemistry? Bidimensional spectroelectroanalysis in presence of an antioxidant compound” 2. AUTHORSHIP: Name: Fabiola Olmo-Alonso Institution: Departamento de Quimica. Universidad de Burgos e-mail: folmo@ubu.es ORCID: 0000-0002-4069-3599 Name: Jesus Garoz-Ruiz Institution: Departamento de Quimica. Universidad de Burgos e-mail: jgarozruiz@ubu.es ORCID: 0000-0002-5775-4247 Name: Aranzazu Heras Institution: Departamento de Quimica. Universidad de Burgos e-mail: maheras@ubu.es ORCID: 0000-0002-5068-2164 Name: Alvaro Colina Institution: Departamento de Quimica. Universidad de Burgos e-mail: acolina@ubu.es ORCID: 0000-0003-0339-356X DESCRIPTION 1. DATASET LANGUAGE: English 2. KEYWORDS: Bidimensional Spectroelectrochemistry, Adrenaline, Ascorbic acid, Quantitative Analysis 3. ABSTRACT: This work demonstrates how the way a chemical system is sampled plays a key role in spectroelectroanalysis, illustrated by the quantification of an analyte in presence of an antioxidant compound. For this purpose, bidimensional spectroelectrochemistry experiments were performed using epinephrine as the model analyte and ascorbic acid as antioxidant and interfering compound, as a proof of concept. This is the first time that three calibration curves are obtained simultaneously on a single spectroelectrochemistry data set, one for the electrochemical signal and two for the optical responses in normal and parallel configurations. The differences between the two optical arrangements, that are related to the diffusion process which is an essential feature for the spectroelectrochemical detection of compounds, have been experimentally demonstrated. As can be observed, the spectral signal in parallel configuration allows us to obtain the best analytical results, since in this configuration only the first micrometers of the solution adjacent to the electrode surface are sampled, thus removing the interfering effect of the antioxidant compound. This fact does not occur with either the electrochemical signal or the spectral response in normal configuration. Furthermore, it has been shown that the parallel configuration provides better results than the normal configuration in terms of sensitivity. In summary, epinephrine is successfully detected in a simple and effective way, even in the presence of a direct antioxidant compound such as ascorbic acid at different concentrations levels, which makes spectroelectrochemistry a good choice for quantitative analysis. 4. DATE OF DATA COLLECTION: 2022 5. DATE OF DATASET PUBLICATION: 29-05-2023 6. FUNDING: Authors acknowledge the financial support given by Ministerio de Ciencia e Innovación and Agencia Estatal de Investigacion (MCIN/AEI/ 10.13039/501100011033, PID2020-113154RB-C21) and Ministerio de Ciencia, Innovacion y Universidades (Grant RED2018-102412-T). Fabiola Olmo is grateful for the contract funded by Junta de Castilla y Leon, the European Social Fund, and the Youth Employment Initiative. ACCESS INFORMATION 1. LICENSE: This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/) 2. Dataset DOI: https://doi.org/10.36443/10259/7683 3. RELATED PUBLICATIONS: Article published in Journal of Electroanalytical Chemistry, 935 (2023) 117333 (Elsevier) https://doi.org/10.1016/j.jelechem.2023.117333 METHODOLOGICAL INFORMATION Commercial SPEs (DRP-110, Metrohm-DropSens), which included a three-electrode configuration printed on the same support, were used to perform all the experiments. Each SPE has a 4 mm diameter disk screen-printed carbon working electrode (WE), a carbon counter electrode (CE) and a silver pseudo-reference electrode (RE). In all experiments, cyclic voltammograms (CVs) corresponding to a first scan, starting at a potential where no electrochemical reaction takes place, are shown. All voltammograms are represented respect to a silver pseudo-reference electrode. For comparison with experiments in literature, a difference of +0.588 V respect to a reversible hydrogen electrode (RHE) is measured using the same supporting electrolyte composition. Two customized SPELEC instruments (Metrohm-DropSens), controlled by DropView SPELEC software (Metrohm-DropSens), were used for the BSEC experiments. bifurcated optical fiber (QBIF600-UV–VIS, Ocean Optics) was connected to the light source. A scheme of the BSEC cell used to perform the experiments is shown in Fig. 1. As can be observed, a reflection probe which consists of 6 illumination optical fibers and a central collection optical fiber was connected to obtain the optical response in normal configuration (FCR-7UV200-2–2.5X100-ME-SR, Avantes). The reflection probe was placed at 1.8 mm from the working electrode using a clamp. In order to obtain the optical response in parallel arrangement, two bare optical fibers (100 um in diameter, Ocean Optics) were aligned face to face on the working electrode at a distance of 0.2 mm. One of the optical fibers was connected to the light source and the other one to the spectrometer. To perform the corresponding measurements, a solution drop (100 uL) was placed on the electrode, covering the three-electrode system and the ends of the reflection probe and the bare optical fibers. In all experiments the initial solution was taken as reference spectrum. Matlab R2018a is the software used for the treatment and analysis of the data generated. FILE OVERVIEW E01_bidim_blanco_CV.csv E01_bidim_blanco_CV_p.csv E02_bidim_AD2_CV.csv E02_bidim_AD2_CV_p.csv E03_bidim_AA0con3_CV.csv E03_bidim_AA0con3_CV_p.csv E04_bidim_AD1_AA0con4_CV.csv E04_bidim_AD1_AA0con4_CV_p.csv E05_bidim_AD3_AA0con4_CV.csv E05_bidim_AD3_AA0con4_CV_p.csv E06_bidim_AD0con5_AA0con3_CV.csv E06_bidim_AD0con5_AA0con3_CV_p.csv E07_bidim_AD0con2_AA0con5_CV.csv E07_bidim_AD0con2_AA0con5_CV_p.csv E08_bidim_AD0con1_AA0con1_CV.csv E08_bidim_AD0con1_AA0con1_CV_p.csv E09_bidim_AD2_AA0con5_CV.csv E09_bidim_AD2_AA0con5_CV_p.csv E10_bidim_AD5_AA0con3_CV.csv E10_bidim_AD5_AA0con3_CV_p.csv E11_bidim_AD4_AA0con5_CV.csv E11_bidim_AD4_AA0con5_CV_p.csv E12_bidim_blanco_CV.csv E12_bidim_blanco_CV_p.csv E10_bidim_AD5_AA0con3_CA.csv E10_bidim_AD5_AA0con3_CA_p.csv E11_bidim_AD4_AA0con5_CA.csv E11_bidim_AD4_AA0con5_CA_p.csv E12_bidim_blanco_CA.csv E12_bidim_blanco_CA_p.csv E13_bidim_blanco_CV.csv E13_bidim_blanco_CV_p.csv E14_bidim_AD2_CV.csv E14_bidim_AD2_CV_p.csv E15_bidim_AA0con5_CV.csv E15_bidim_AA0con5_CV_p.csv E16_bidim_AD2_AA0con5_CV.csv E16_bidim_AD2_AA0con5_CV_p.csv E17_bidim_AD2_AA0con5_CV.csv E17_bidim_AD2_AA0con5_CV_p.csv DATA-SPECIFIC INFORMATION Each “.csv” experiment includes a file with a matrix that include information about time, potential, current, wavelength and intensity.