Figure 4.

Array-based sensing of eight proteins in 10 mM Tris-HCl (pH 7.4) and five proteins in human serum. (a) Absorbance response (ΔA, A - A₀) patterns of the ssDNA-AuNPs-GO sensor array (NP1-NP5) against various proteins at 0.5 nM concentration: bovine serum albumin (BSA), cytochrome c (Cyto), hemoglobin (Hb), lysozyme (Lyso), horseradish peroxidase (HRP), myoglobin (Mb), transferrin (Tf) and thrombin (Th). Error bars represent standard deviations of six parallel measurements. (b) Canonical score plot for the absorbance response patterns as obtained from LDA against eight proteins at a constant concentration of 0.5 nM, with 95% confidence ellipses. (c) Absorbance response (ΔA) patterns of the ssDNA-AuNPs-GO sensor array (NP1-NP5) against five proteins (BSA, Lyso, Cyto, Hb, and Mb) spiked in human serum at 10 nM concentration. Error bars represent standard deviations of six parallel measurements. (d) Canonical score plot for the absorbance response patterns as obtained from LDA against five proteins at a fixed concentration of 10 nM, with 95% confidence ellipses. All five proteins can be well-separated and properly identified.