Advanced green electrochemical pH sensor using phyto-cardamom modified electrode

Given the shortcomings associated with traditional glass pH electrodes, including fragility, errors in detection in the alkaline ranges, laborious fabrication steps, and use of costly materials, there is a paradigm shift toward cost-effective, accurate, and durable redox-active electrochemical pH sensors. This work introduces a green synthesis protocol via electrochemical anchoring of phyto-cardamom onto a multiwalled carbon nanotube-coated glassy carbon electrode (GC/MW@CA) as an electrochemical pH sensor, effective across both acidic and alkaline ranges. The sensor revealed high surface roughness, distinct redox behavior, improved electron transfer, fast response time, and anti-interferent properties. The superior electrochemical response of the sensor, specific to each pH value, was established using CV and DPV studies, displaying a clear shift in the peak potentials with the varying pH. Real sample analysis with fruit juices, saliva, and std. buffer solution employing a three-in-one screen-printed electrode (SPE), showed <2% relative error, proving the high reliability and accuracy of the developed sensor for real-world applications.