Paper-based microfluidic device with a gold nanoparticle sensor for arsenic detection applied to groundwater in Bangladesh

Abstract

This study demonstrates the development of a paper-based microfluidic device (μPAD) with a gold nanosensor (Au-TA-TG) to detect arsenic contamination in Bangladesh groundwater at the World Health Organization (WHO) guideline level (10 μg/L). A method has also been developed to prevent interference from alkaline metals (Ca, Mg, K and Na) by altering the pH level on the μPADs. The heavy metals present in groundwater (Mn, Pb, Ni, Cd, Fe III and Fe II) are also confirmed no interference with the μPAD arsenic tests. Except for Fe III, which the villagers already remove from their groundwater. The μPADs are also tested with 24 groundwater samples collected from hand tubewells in three different regions in Bangladesh: Shirajganj, Manikganj, and Munshiganj, and the results agreed with the results obtained from laboratory testing. The μPAD arsenic test can provide the first easy-to-read test and capable of detecting arsenic at the WHO guideline level (10 μg/L). Thus villagers can test their own water sources and be empowered to make decisions about where to obtain the safest water.