Development of an Inkjet-Printed Sensor Using Ink Locked Food-Based Nano Conductive Paste for Electrochemical Sensing of Insulin: a First Attempt

This work introduces the first inkjet-printed electrochemical sensor utilizing a food-based nano conductive paste (FN-CoP) for insulin detection. FN-CoP, composed of activated charcoal, vegetable gelatin, and oral rehydration salts, is developed in-house as an eco-friendly and biocompatible alternative to traditional carbon pastes. Inkjet printing allows for precise electrode patterning while minimizing material waste. FN-CoP demonstrates high conductivity (<tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$1484 ~\mathrm{S} / \mathrm{m}$</tex>) and when validated for electrochemical insulin sensing, it shows excellent sensitivity, with a limit of detection (LoD) of 1.8 pM. Its strong adhesion and compatibility across various substrates (glass, polyamide, cloth) indicate its potential for broader applications in biosensing and energy-related technologies.