Next Article in Journal
Investigation on Magnetic Field Usage for Urban Water Treatment
Previous Article in Journal
From Characterisation to Validation: A Journey through Master’s Level Analytical Chemistry
Font Type:
Arial Georgia Verdana
Font Size:
Aa Aa Aa
Line Spacing:
Column Width:
Proceeding Paper

Assessment of the Dynamic Parameters of an Ion-Selective Microsensor †

Faculty of Applied Chemistry and Materials Science, University Politehnica of Bucharest, 1-7 Polizu St., sector 1, 011061 Bucharest, Romania
Department of Bioengineering, Faculty of Chemical and Metallurgical Engineering, Yildiz Technical University, 34210 Esenler-Istanbul, Turkey
School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne (EPFL), Route Cantonale, 1015 Lausanne, Switzerland
Bioengineering Department, Istanbul Medeniyet University, Goztepe, 34700 Istanbul, Turkey
Author to whom correspondence should be addressed.
Presented at the Virtual Eurachem Workshop 2020—“Quality Assurance for Analytical Laboratories in the University Curriculum”, 14–15 July 2020; Available online:
Proceedings 2020, 55(1), 13;
Published: 9 October 2020


We report the statistical parameters associated with the dynamic characteristics of a calcium microelectrode. The electrochemical behavior of the obtained microsensor was assessed against the main interferents.

1. Introduction

Selective ion microelectrodes with selective membranes as sensitive elements are used in many applications in industrial environments, environmental protection, or clinical studies [1,2,3].
The impressive development of new technologies for the realization of microstructures and the reduced manufacturing costs have recommended, in recent years, the use of microsensors, especially in situations where the use of minimal amounts of an analyte is required. At the same time, the tendency to achieve selective ion membranes that are subsequently compatible with microtechnology, due to the need to expand the use of miniaturized ion selective electrodes (ISE), should be noted [4,5,6].
Selective microsensors are characterized through a specific dynamic behavior in complex matrices when interfering ions are present. In analytical laboratories, the determination of the dynamic electrochemical characteristics of the sensing devices is essential. The current work introduces the statistical assessment of the dynamic features for a calcium microelectrode.

2. Experimental

The used electrochemical system consisted of a carbon paste solid-contact electrochemical calcium microsensor and a homemade solid-state Ag/AgCl as a micro-reference electrode [7]. The determinations were performed with the help of a multichannel MEDISEN type IEMS-4 potentiometric system, provided by Medisen Medikal Teknolojiler Araştırma Geliştirme San. Tic. Ltd. Şti., Turkey. The electrochemical behavior was studied for calcium solutions over a broad concentration range 10−1 to 10−6 mol/L and in the presence of the interfering ions: magnesium, potassium, lithium, sodium, ammonium, and barium (10−2 mol/L).

3. Results and Discussion

The tested calcium microelectrode presented a Nernstian electrochemical answer over the whole concentration range (26.8 ± 0.3 mV/decade). In the presence of the interfering ions, the microelectrode exhibited a reproducible and highly selective response. The selectivity coefficients (logKCa, i) ranged from −3.62 for Mg2+ to −4.51 for NH4+, highlighting the satisfactory selectivity of the sensing device. Moreover, the fast response time (6.0 ± 0.2 s) qualifies the solid-state microsensor for applications where a fast and accurate electrochemical response is required.
The repeatability parameter completed the assessment of the main dynamic characteristics as electrochemical response, selectivity, detection limit (3.2 × 10−6 mol/L), and response time. The determined values supported the reliability of the calcium microsensor.
The statistical parameters calculated for the mean potentials recorded at different concentrations (10−2 mol/L, 10−3 mol/L, 10−4 mol/L) evidenced a low standard deviation (0.98, 0.43, 0.38), respectively, and a standard deviation of the mean (0.20, 0.09, 0.08)—see Figure 1. The low values for the statistical parameters signify the high reliability of the recorded experimental data.
The study of the electrochemical potential variation over a pH range between four and nine for the calcium microelectrode showed no significant variation (maximum 7 mV).

4. Conclusions

The electrochemical dynamic characteristics and the assessment of the statistical parameters for the calcium microelectrode indicate that the sensing device could be successfully used for the study of complex matrices (clinical or environmental) where a quick and reliable determination of the calcium ion levels is requested.

Author Contributions

Conceptualization, E.E.T., I.I. and O.T.; methodology, E.E.T., I.A., M.N. and T.T.; software, T.T.; validation, E.E.T., I.I., S.I. and T.T.; formal analysis, R.Y. and M.N.; investigation, E.E.T., S.I., D.C.P., O.T., M.N., R.Y. and I.A.; data curation, T.T.; writing—original draft preparation, E.E.T.; writing—review and editing, E.E.T. and I.I.


This work was supported by a grant from the Advisory Board for Research, Development and Innovation-Executive Unit for Financing Higher Education, Research, Development and Innovation CCCDI–UEFISCDI, project number 39/2018 COFUND-MANUNETIII- HAMELDENT, within National Plan for Research-Development and Innovation-PNCDIIII, and a grant from the Scientific and Technological Research Council of Turkey (TÜBITAK), grant no: BIYOTEG-9170032.

Conflicts of Interest

The authors declare no conflict of interest.


  1. Tseng, K.-W.; Hsiao, Y.-P.; Jen, C.-P.; Chang, T.-S.; Wang, H.-C. Cu2O/PEDOT: PSS/ZnO Nanocomposite Material Biosensor for Esophageal Cancer Detection. Sensors 2020, 20, 2455. [Google Scholar] [CrossRef] [PubMed]
  2. Totu, E.E.; Mănuc, D. Multisensor for Clinical Analysis with Impact on Public Health Evaluation. Rev. Chim. 2008, 59, 947–951. [Google Scholar] [CrossRef]
  3. Lee, C.W.; Suh, J.M.; Jang, H.W. Chemical Sensors Based on Two-Dimensional (2D) Materials for Selective Detection of Ions and Molecules in Liquid. Front. Chem. 2019, 7, 708. [Google Scholar] [CrossRef] [PubMed]
  4. Totu, E.E.; Isildak, I.; Nechifor, A.C.; Cristache, C.M.; Enachescu, M. New sensor based on membranes with magnetic nano-inclusions for early diagnosis in periodontal disease. Biosens. Bioelectron. 2018, 102, 336–344. [Google Scholar] [CrossRef] [PubMed]
  5. Kańtoch, E. Recognition of Sedentary Behavior by Machine Learning Analysis of Wearable Sensors during Activities of Daily Living for Telemedical Assessment of Cardiovascular Risk. Sensors 2018, 18, 3219. [Google Scholar] [CrossRef] [PubMed]
  6. Bandodkar, A.J.; Jeerapan, I.; Wang, J. Wearable Chemical Sensors: Present Challenges and Future Prospects. ACS Sens. 2016, 1, 464–482. [Google Scholar] [CrossRef]
  7. Totu, E.E.; Isildak, I.; Tavukcuoglu, O.; Agir, I.; Yildirim, R.; Nigde, M.; Nechifor, A.C.; Cristache, C.M. Coated copper wire calcium selective microelectrode for applications in dental medicine. Rev. Chim. 2018, 69, 4113–4117. [Google Scholar] [CrossRef]
Figure 1. (a) Mean potential; (b) statistical parameters.
Figure 1. (a) Mean potential; (b) statistical parameters.
Proceedings 55 00013 g001
Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Share and Cite

MDPI and ACS Style

Totu, E.E.; Isildak, I.; Petre, D.C.; Işildak, S.; Niğde, M.; Tavukçuoğlu, Ö.; Yildirim, R.; Totu, T.; Ağır, I. Assessment of the Dynamic Parameters of an Ion-Selective Microsensor. Proceedings 2020, 55, 13.

AMA Style

Totu EE, Isildak I, Petre DC, Işildak S, Niğde M, Tavukçuoğlu Ö, Yildirim R, Totu T, Ağır I. Assessment of the Dynamic Parameters of an Ion-Selective Microsensor. Proceedings. 2020; 55(1):13.

Chicago/Turabian Style

Totu, Eugenia Eftimie, Ibrahim Isildak, Daniel Costinel Petre, Selim Işildak, Mustafa Niğde, Özlem Tavukçuoğlu, Ridvan Yildirim, Tiberiu Totu, and Ismail Ağır. 2020. "Assessment of the Dynamic Parameters of an Ion-Selective Microsensor" Proceedings 55, no. 1: 13.

Article Metrics

Back to TopTop