Effect of DNA serial dilution on the highly precise broadband plasmonic signature of a BALB/c rat’s dried DNA deposited on gold thin film

Abstract

An investigation was made to detect the DNA samples of BALB/c rats, exploiting the technique of broadband plasmonic response in the visible spectral regime. In experiments, a non-coherent light beam was physically designed and practically implemented to study the spectral effect due to serial dilution of BALB/c rat’s dried DNA. In particular, three different diluted DNA samples (with ratios of 1:10, 1:20, and 1:40) dried on the surface of a nanolayer gold thin film were considered to retrieve the plasmonic conditions under which the reflectance becomes minimum. The results indicate the most diluted DNA sample exhibits prominent plasmonic conditions, and the resonance wavelengths undergo redshifts with increasing incidence angle (of the p-polarized light). Also, the sensitivity of the configuration is enhanced in the presence of a DNA sample (as compared to the case of non-existence of measurand), which is further increased for larger incidence angles.