TY  - JOUR
AU  - Švorc, Lubomir
AU  - Haššo, Marek
AU  - Sarakhman, Olha
AU  - Kianičkova, Kristina
AU  - Stanković, Dalibor M.
AU  - Otrisal, Pavel
PY  - 2018
UR  - https://linkinghub.elsevier.com/retrieve/pii/S0026265X18307367
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/7791
AB  - In the present paper, a miniaturized boron-doped diamond electrode (BDDE) is proposed as a progressive electrochemical sensor for simple, fast and reliable quantification of dimethylxanthine alkaloid, theobromine (TB). Using cyclic voltammetry, the studied xanthine provided one well-shaped, irreversible and diffusion-controlled oxidation peak at relatively high potentials (+1.2 V vs. Ag/AgCl/3 M KCl reference electrode) in the presence of 0.1 M H2SO4. After selection of suitable experimental conditions, the linear calibration curves for TB were obtained in the concentration range from 0.99 up to 54.5 μM with the sensitivity of 0.07 μA/μM providing both differential pulse (DPV) and square-wave voltammetric (SWV) techniques, respectively. The elaborated voltammetric protocol yielded low detection limits of 0.42 and 0.51 μM accompanied by adequate intra-day repeatability (relative standard deviation of 2.5 and 1.7%) using DPV and SWV procedure, respectively. The interference study revealed the reasonable selectivity when taking the target food samples into account. The practical applicability of the voltammetric protocol using a miniaturized BDDE was verified in the analysis of six commercially available brands of chocolate products with the determined mass percentages of TB ranging from 0.75 to 2.24% and from 0.69 to 2.15% using DPV and SWV procedure, respectively. The obtained results were also in a good agreement with those achieved by reference titration method with potentiometric indication. The progressive electrochemical sensor based on a miniaturized BDDE has appeared to be an attractive candidate for practical applications in food quality control. Besides, the proposed voltammetric protocol presents advantages when compared to others techniques (e.g. chromatography), concerning simplicity, cost, speed of analysis, waste generation (environmentally friendly) and samples pretreatment (only dilution in electrolyte solution prior to analysis). © 2018 Elsevier B.V.
T2  - Microchemical Journal
T1  - A progressive electrochemical sensor for food quality control: Reliable determination of theobromine in chocolate products using a miniaturized boron-doped diamond electrode
VL  - 142
SP  - 297
EP  - 304
DO  - 10.1016/j.microc.2018.07.007
ER  - 

@article{
author = "Švorc, Lubomir and Haššo, Marek and Sarakhman, Olha and Kianičkova, Kristina and Stanković, Dalibor M. and Otrisal, Pavel",
year = "2018",
abstract = "In the present paper, a miniaturized boron-doped diamond electrode (BDDE) is proposed as a progressive electrochemical sensor for simple, fast and reliable quantification of dimethylxanthine alkaloid, theobromine (TB). Using cyclic voltammetry, the studied xanthine provided one well-shaped, irreversible and diffusion-controlled oxidation peak at relatively high potentials (+1.2 V vs. Ag/AgCl/3 M KCl reference electrode) in the presence of 0.1 M H2SO4. After selection of suitable experimental conditions, the linear calibration curves for TB were obtained in the concentration range from 0.99 up to 54.5 μM with the sensitivity of 0.07 μA/μM providing both differential pulse (DPV) and square-wave voltammetric (SWV) techniques, respectively. The elaborated voltammetric protocol yielded low detection limits of 0.42 and 0.51 μM accompanied by adequate intra-day repeatability (relative standard deviation of 2.5 and 1.7%) using DPV and SWV procedure, respectively. The interference study revealed the reasonable selectivity when taking the target food samples into account. The practical applicability of the voltammetric protocol using a miniaturized BDDE was verified in the analysis of six commercially available brands of chocolate products with the determined mass percentages of TB ranging from 0.75 to 2.24% and from 0.69 to 2.15% using DPV and SWV procedure, respectively. The obtained results were also in a good agreement with those achieved by reference titration method with potentiometric indication. The progressive electrochemical sensor based on a miniaturized BDDE has appeared to be an attractive candidate for practical applications in food quality control. Besides, the proposed voltammetric protocol presents advantages when compared to others techniques (e.g. chromatography), concerning simplicity, cost, speed of analysis, waste generation (environmentally friendly) and samples pretreatment (only dilution in electrolyte solution prior to analysis). © 2018 Elsevier B.V.",
journal = "Microchemical Journal",
title = "A progressive electrochemical sensor for food quality control: Reliable determination of theobromine in chocolate products using a miniaturized boron-doped diamond electrode",
volume = "142",
pages = "297-304",
doi = "10.1016/j.microc.2018.07.007"
}

Švorc, L., Haššo, M., Sarakhman, O., Kianičkova, K., Stanković, D. M.,& Otrisal, P.. (2018). A progressive electrochemical sensor for food quality control: Reliable determination of theobromine in chocolate products using a miniaturized boron-doped diamond electrode. in Microchemical Journal, 142, 297-304.
https://doi.org/10.1016/j.microc.2018.07.007

Švorc L, Haššo M, Sarakhman O, Kianičkova K, Stanković DM, Otrisal P. A progressive electrochemical sensor for food quality control: Reliable determination of theobromine in chocolate products using a miniaturized boron-doped diamond electrode. in Microchemical Journal. 2018;142:297-304.
doi:10.1016/j.microc.2018.07.007 .

Švorc, Lubomir, Haššo, Marek, Sarakhman, Olha, Kianičkova, Kristina, Stanković, Dalibor M., Otrisal, Pavel, "A progressive electrochemical sensor for food quality control: Reliable determination of theobromine in chocolate products using a miniaturized boron-doped diamond electrode" in Microchemical Journal, 142 (2018):297-304,
https://doi.org/10.1016/j.microc.2018.07.007 . .