Colorimetric sensor for Zn(III) using induced aggregation of functionalized gold nanoparticles

In order to meet the future needs in chemosensors, fundamental nanoscopic understanding and development over traditional techniques could be accomplished. The current conventional methods for the detection of heavy metal ions require complicated and expensive instrumentation. Thus, rapid and sensitive detection of selective metal ions with inexpensive equipment should be developed (i.e., with a low cost UV–Vis spectrometer or naked-eye detection). We have demonstrated a colorimetric sensor that can selectively discriminate Zn(II) in aqueous media. The colorimetric sensor was utilized by functionalizing the surface of gold nanoparticles with bis(pyridine-2-ylmethyl) phenyl group ( 1-AuNPs). By analyzing with 10 different metal ions, 1-AuNPs showed a selective visual detection of Zn(II) with an excellent detection limit of 2 ppm.