Simple Colorimetric Detection of Amyloid<i>β</i>-peptide (1-40) based on Aggregation of Gold Nanoparticles in the Presence of Copper Ions

A simple method for specific colorimetric sensing of Alzheimer's disease related amyloid-β peptide (Aβ) is developed based on the aggregation of gold nanoparticles in the presence of copper ion. The detection of limit for Aβ(1-40) is 0.6 nM and the promising results from practical samples (human serum) indicate the great potential for the routine detection.