Colorimetric sensor for Pb detection in water using thioglycolic acid-conjugated gold nanoparticles.

Environmental pollution by the heavy metal lead (Pb) poses significant health risks, including kidney damage and neurotoxicity in children. Gold nanoparticles (AuNPs) have shown promise as colorimetric sensors for visually detecting Pb through surface plasmon resonance. This study developed a colorimetric method using thioglycolic acid (TGA) as a conjugate, leveraging its strong S-Au bond and carboxyl group to enhance AuNPs stability and Pb specificity.