Green Synthesis of Silver Nanoparticles (AgNPs) Using Polyvinyl Alcohol (PVA)-Modified Andrographis paniculata Leaf Extract for Mercury (Hg2+) Colorimetric Sensing

Arah Guntur Guntur (a:1:{s:5:"en_US"s:22:"UPN Veteran Jawa Timur"})
Akmalia Dinda Oktavianta Oktavianta (Department of Chemical Engineering, Faculty of Engineering and Science, Universitas Pembangunan Nasional “Veteran” Jawa Timur, Indonesia)
Ketut Sumada (Department of Chemical Engineering, Faculty of Engineering and Science, Universitas Pembangunan Nasional “Veteran” Jawa Timur, Indonesia)
Sani Sani (Department of Chemical Engineering, Faculty of Engineering and Science, Universitas Pembangunan Nasional “Veteran” Jawa Timur, Indonesia)
Caecilia Pujiastuti (Department of Chemical Engineering, Faculty of Engineering and Science, Universitas Pembangunan Nasional “Veteran” Jawa Timur, Indonesia)

AJARCDE (Asian Journal of Applied Research for Community Development and Empowerment)
Vol. 10 No. 3 (2026)

Mercury (Hg2+) contamination is a serious environmental issue due to its toxicity and persistence. This study reports the green synthesis of silver nanoparticles (AgNPs) using Andrographis paniculata leaf extract with poly(vinyl alcohol) (PVA) as a capping agent, and evaluates their application as a colorimetric sensor for Hg2+. detection. AgNPs were synthesized using varying AgNO3 (0.5–2.5 mM) and PVA (0.1–1.0%) concentrations and characterized by FTIR and UV–Vis spectroscopy. FTIR confirmed functional groups involved in the reduction of Ag+ to Ag0, while UV–Vis spectra showed LSPR peaks at 411–448.5 nm, indicating successful nanoparticle formation. The optimum condition was obtained at 2 mM AgNO3 and 0.4% PVA, with a maximum absorbance of 0.710 at 435.5 nm. The AgNPs exhibited a clear colorimetric response to Hg2+, changing from yellowish-brown to colorless. These results highlight the potential of A. paniculata-based AgNPs as an eco-friendly and cost-effective sensor for mercury detection.