Cadmium and nickel in industrial wastewater are harmful to human health and the environment, and current testing methods are expensive, slow, and require laboratory equipment. To address this, the research team of Assist. Prof. Dr. Pumidech Puthongkham and Dr. Nadnudda Rodthongkum created a special conductive hydrogel made from polyaniline (a conductive polymer), cellulose nanofibers (from plant adsorbent material), and polyvinyl alcohol (a common, safe synthetic polymer). This hydrogel was placed on a screen-printed graphene electrode, making the sensor highly sensitive and suitable for quick, on-site testing. The sensor can detect metal concentrations as low as 2 ppb for cadmium and 6 ppb for nickel — well below safety limits. It also performed well in real industrial wastewater samples, with results matching traditional lab methods. This innovation based on flexible conductive substrate could help industries and environmental agencies monitor water quality more easily.
- Pichapon Boonkrong
- Nadtinan Promphet
- Nadnudda Rodthongkum
- Pumidech Puthongkham