Multidimensional Sensor for Pattern Recognition of Proteins Based on DNA-Gold Nanoparticles Conjugates

We presented an extensible multidimensional sensor with conjugated nonspecific dye-labeled DNA sequences absorbed onto gold nanoparticles (DNA–AuNPs) as receptors. At the presence of target protein, DNA was removed from the surface of AuNPs due to the competitive binding, which resulted in a red-to-blue color change along with salt-induced aggregation of AuNPs for colorimetric analysis and fluorescent “turn-on” signal of the labeled dye for fluorescence analysis. The orthogonal and complementary fluorescent and colorimetric signals obtained from each protein were applied to distinguish different proteins. By simply changing the DNA sequences, more dual-channel sensing elements could be easily obtained and added into this multidimensional sensor. This enhanced its discriminating power to the proteins. With three sensing elements, our extensible multidimensional sensing platform exhibited excellent discrimination ability. Eleven proteins at the concentration of 50 nM had been classified with accuracies of 1...