Detection of Cu²⁺ Ions with GGH Peptide Realized with Si-Nanoribbon ISFET

• Main Authors: Olena Synhaivska, Yves Mermoud, Masoud Baghernejad, Israel Alshanski, Mattan Hurevich, Shlomo Yitzchaik, Mathias Wipf, Michel Calame
• Format: Article
• Language: English
• Published: MDPI AG 2019-09-01
• Series: Sensors
• Subjects: potentiometric sensing; copper; GGH peptide; ion-sensitive field effect transistor; silicon nanoribbons
• Online Access: https://www.mdpi.com/1424-8220/19/18/4022

The presence of heavy metal ions such as copper in the human body at certain concentrations and specific conditions can lead to the development of different diseases. The currently available analytical detection methods remain expensive, time-consuming, and often require sample pre-treatment. The development of specific and quantitative, easy-in-operation, and cost-effective devices, capable of monitoring the level of Cu²⁺ ions in environmental and physiological media, is necessary. We use silicon nanoribbon (SiNR) ion-sensitive field effect transistor (ISFET) devices modified with a Gly−Gly−His peptide for the detection of copper ions in a large concentration range. The specific binding of copper ions causes a conformational change of the ligand, and a deprotonation of secondary amine groups. By performing differential measurements, we gain a deeper insight into the details of the ion−ligand interaction. We highlight in particular the importance of considering non-specific interactions to explain the sensors’ response.