Rapid prototyping of ion-selective electrodes using a low-cost 3D printed internet-of-things (IoT) controlled robot

ÖZER T. , Agir I., Henry C. S.

Talanta, vol.247, 2022 (Journal Indexed in SCI) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 247
  • Publication Date: 2022
  • Doi Number: 10.1016/j.talanta.2022.123544
  • Title of Journal : Talanta
  • Keywords: 3D-printing, Internet-of-things (IoT), Solid-contact ion-selective electrode, Potassium, Sodium, Potentiometric detection, Point-of-care, IMPRINTED MESOPOROUS CARBON, SOLID-CONTACT, WATER LAYER, SENSOR, HYPONATREMIA, DISORDERS, URINE


© 2022 Elsevier B.V.We report automated fabrication of solid-contact sodium-selective (Na+-ISEs) and potassium-selective electrodes (K+-ISEs) using a 3D printed liquid handling robot controlled with Internet of Things (IoT) technology. The printing system is affordable and can be customized for the use with micropipettes for applications such as drop-casting, biological assays, sample preparation, rinsing, cell culture, and online analyte monitoring using multi-well plates. The robot is more compact (25 × 30 × 35 cm) and user-friendly than commercially available systems and does not require mechatronic experience. For fabrication of ion-selective electrodes, a carbon black intermediate layer and ion-selective membrane were successively drop-cast on the surface of stencil-printed carbon electrode using the dispensing robot. The 3D-printed robot increased ISE robustness while decreasing the modification time by eliminating manual steps. The Na+-ISEs and K+-ISEs were characterized for their potentiometric responses using a custom-made, low-cost (<$25) multi-channel smartphone-based potentiometer capable of signal processing and wireless data transmission. The electrodes showed Nernstian responses of 58.2 ± 2.6 mV decade−1 and 56.1 ± 0.7 mV decade−1 for Na+ and K+, respectively with an LOD of 1.0 × 10−5 M. We successfully applied the ISEs for multiplexed detection of Na+ and K+ in urine and artificial sweat samples at clinically relevant concentration ranges. The 3D-printed pipetting robot cost $100 and will pave the way for more accessible mass production of ISEs for those who cannot afford the expensive commercial robots.