Green Silver Nanoparticles Based Multi-Technique Sensor for Environmental Hazardous Cu(II) Ion

Abstract

In the present work, we report green synthesized unmodified silver nanoparticles from Moringa oleifera’s bark extract (AgNP-MO) as multifunctional sensor for hazardous Cu(II) ion with high selectivity. The optical and fluorescent sensing of Cu(II) ion in presence of AgNP-MO was investigated and optimized. The intensity of SPR absorption band of AgNP-MO dramatically reduced with Cu(II) ion concentration as a result of complex formation, and it could be recognized by naked eye with a visual detection. The electrochemical activity of silver nanoparticles was explored for the sensing of Cu(II) ion by AgNP-MO-modified platinum electrode (AgNP-MO/PE). The Cu(II) ion selectivity of the developed system was investigated by both techniques. The applicability of developed electrochemical sensor was checked with water samples collected from Vembanad Lake, Kumarakom, Kottayam, Kerala, and electroplating industry. The limit of detection of a developed sensor for Cu(II) ion detection was found at 0.530 μM. The antibacterial activity of silver nanoparticles from Moringa oleifera was checked against with two waterborne bacteria extracted from the same lake water sample. To the best of our knowledge, there are no reports for the electrochemical sensing of Cu(II) ion by AgNP-MO/PE. We expect our present approach to have multifunctional applications in various areas.