Investigating Economic Methods for the Detection of Lead Ions in Drinking Water

We aim to develop two economic methods to detect lead ions in drinking water. One is to synthesize bismuth nanoparticles to replace gold and silver nanoparticles used in surface-enhanced Raman spectroscopy. The other is the applicability of using 4-aminothiophenol (4-ATP) to directly react with lead ions. For bismuth nanoparticle synthesis, we successfully used lemon juice as both a reduction and capping agent, which helps to serve as a green alternative to traditional nanoparticle synthesis. The diameter of the bismuth nanoparticles were found to be around 50 nm through scanning electron microscopy characterization. As for the 4-ATP method, we found that lead ions and 4-ATP react to form a visible shard-like precipitate as well as a much smaller branch-like precipitate that sticks to microscope substrates. Light microscope images showed differences in the amount and morphology of the precipitates as the concentration of lead was changed from 25 μM to 2.5 μM. These findings will help us to further utilize bismuth nanoparticles for Raman spectroscopy and to understand the reactions between 4-ATP and lead ions for assessing lead ions in water.