Electrochemical Sodium Ion Sensor Based on Silver Nanoparticles/Graphene Oxide Nanocomposite for Food Application

• Main Authors: Pranlekha Traiwatcharanon, Wilai Siriwatcharapiboon, Chatchawal Wongchoosuk
• Format: Article
• Language: English
• Published: MDPI AG 2020-07-01
• Series: Chemosensors
• Subjects: AgNPs; graphene oxide; AgNPs/GO; electrochemical sensor; sodium ion detection; sensor for food application
• Online Access: https://www.mdpi.com/2227-9040/8/3/58

High sodium ion (Na⁺) consumption leads to high blood pressure which causes many health issues. Real-time determination of Na⁺ content in food is still important to limit Na⁺ intake and control the taste of food. In this work, we have developed an electrochemical sensor based on agglomeration of silver nanoparticles (AgNPs) and graphene oxide (GO) modified on a screen-printed silver electrode (SPE) for Na⁺ detection at room temperature by using cyclic voltammetry (CV). The AgNPs were synthesized through a simple green route using <i>Pistia stratiotes</i> extract as a reducing agent under blue light illumination and mixed with the GO to be a Na⁺ selective sensing nanocomposite. The AgNPs/GO/SPE sensor showed high sensitivity (0.269 mA/mM/cm²), high selectivity, linear relationship (0–100 mM), good stability, and excellent reproducibility to Na⁺ detection as well as low limit of detection (9.344 mM) for food application. The interfering species such as K⁺, Zn²⁺, Na⁺, Mg²⁺, glucose, and ascorbic acid did not have any influence on the Na⁺ determination. The AgNPs/GO/SPE sensor was successfully applied to determine Na⁺ in real samples such as fish sauce and seasoning powder of instant noodle.