Erturan, Ahmet MuratDurmaz, HabibeGültekin, Seyfettin Sinan2023-08-032023-08-0320230038-70101532-2289https://doi.org/10.1080/00387010.2023.2208650https://hdl.handle.net/20.500.13091/4350Article; Early AccessBiomolecule detection has become important in many applications such as medical diagnosis, forensic analysis, basic biological studies, and food quality assessment. In particular, the Mid-infrared range offers an important opportunity for biomolecular sensing as it covers the molecular vibrational spectra of vital biochemicals such as Deoxyribonucleic acid, Ribonucleic Acid, and proteins. In this study, a double band absorbing plasmonic nanoantenna array with two gold disk resonators is proposed. The biosensing ability of this structure was investigated using the protein-goat anti-mouse immunoglobulin G model and Polymethyl methacrylate film. The basic structural bonds of protein monolayer, namely Amide-I, Amide-II, and Amide-III showed vibrational signatures at 6010 nm (similar to 1664 cm(-1)), 6496 nm (similar to 1539 cm(-1)), and 6989 nm (similar to 1431 cm(-1)) wavelengths, respectively. In addition, the spectral response of the proposed antenna structure was investigated using a Polymethyl methacrylate film by detecting the C=O and the C-H bonds. The strong dipole moment at C=O showed a strong absorption deep at 5782 nm (similar to 1730 cm(-1)) while the C-H bond has shown a relatively low absorption deep at 3350 nm (similar to 2985 cm(-1)) and 3395 nm (similar to 2946 cm(-1)). Our findings indicate that the double spacer disk configuration detects the spectral signature of the protein monolayer and Polymethyl methacrylate film in each band, simultaneously. The dual-band can be tuned independently by carefully engineering the radii of the double disks without making an effect on the other band. The proposed structure can be used as a characterization tool for identifying unknown complex molecules by simply detecting their spectral fingerprints in each mode of the dual-band, independently. Also, this design strategy can be insight to multi-mode SEIRA platforms, where more complex chemical molecules are needed to be detected or identified in biology, chemistry, and defense areas.eninfo:eu-repo/semantics/closedAccessMetamaterialsplasmonic sensorspolymethyl methacrylate film detectionprotein detectionsurface-enhanced infrared absorptionPerfect AbsorberArticle10.1080/00387010.2023.22086502-s2.0-85158954351