In this study, a bifunctional A beta aggregation inhibitor peptide, GGHRYYAAFFARR (GR), with the abilities to bind copper and antiamyloid was designed to inhibit the neurotoxicity of the A beta-Cu(II) complex. The thioflavin T (ThT) assay, turbidimetric analysis, transmission electron microscopy (TEM), and (344,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) (MTT) assay were used to study its potential inhibitory effect on A beta aggregation. Our findings indicate that GGH was the specific chelating sequence and that the RYYAAFFARR (RR) component acted as an aggregation inhibitor. More importantly, GR significantly decreased the cytotoxicity of the A beta-Cu(II) complex. The cell viability improved to 88%, which was higher than with the single functional peptide GGH and RR by 39% and 20%, respectively. Moreover, the qualitative effect of Cu(II) on the A beta-Cu(II) complex was also studied. Our results indicate that Cu(II) induces the formation of the beta-sheet structure with a subequimolar Cu(II):A beta molar ratio (0.25:1) but led to increased ROS production at a supra-equimolar ratio.