A smartphone-assisted hybrid sensor for simultaneous potentiometric and distance-based detection of electrolytes

Phoonsawat K., AĞIR İ., Dungchai W., Ozer T., Henry C. S.

ANALYTICA CHIMICA ACTA, vol.1226, 2022 (SCI-Expanded) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 1226
  • Publication Date: 2022
  • Doi Number: 10.1016/j.aca.2022.340245
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, Aerospace Database, Aqualine, Aquatic Science & Fisheries Abstracts (ASFA), Artic & Antarctic Regions, BIOSIS, Biotechnology Research Abstracts, CAB Abstracts, Chemical Abstracts Core, Chimica, Communication Abstracts, Compendex, EMBASE, Food Science & Technology Abstracts, MEDLINE, Metadex, Pollution Abstracts, Veterinary Science Database, Civil Engineering Abstracts
  • Keywords: Distance -based paper device, Colorimetric detection, Potentiometric ion -selective electrode, Chloride, Potassium, Point-of-care, SELECTIVE ELECTRODES, QUANTIFICATION, DEVICE, CARBON, IONS, ACID
  • Yıldız Technical University Affiliated: Yes


At home electrolyte analysis is of growing interest due to the importance for early diagnosis for various diseases. This work presents the first device that integrates a potentiometric ion-selective electrode (ISE) with distance -based colorimetric detection for the simultaneous analysis of K+ and Cl(- )ions at the point of care (POC). This hybrid sensing device was designed in a two-dimensional configuration using a plastic transparency sheet containing a stencil printed K+-ISE and a paper substrate for distance-based colorimetric detection of Cl-. K+ quantification was performed using a low-cost (<$25) lab-made Wi-Fi supported potentiometer with a custom smartphone application while Cl- ions were quantified with an instrument-free distance-based paper analytical device (dPAD). The total analysis time is 5 min once the sample is added. The K+-ISE showed a sensitivity of 55.89 +/- 2.52 mV/decade from 0.1 to 100 mM with a limit of detection (LOD) of 0.01 mM. The linear working range for Cl- detection was 0.5-50 mM whereas the LOD was 0.16 +/- 0.05 mM. The proof-of-concept application of the sensing hybrid device was demonstrated in human urine and artificial sweat samples containing K+ and Cl- ions at physiologically relevant ranges. The recoveries were found to be 88-108% for K+ and 90-104% for Cl(-)showing the potential use of the proposed device for low-cost routine analysis of biological samples at POC.