Low concentration protein detection using novel SERS devices

We report, herein, novel processes of nanofabrication techniques for few molecules detection by generating surface plasmons, thus giving a giant electric field in a controllable and reproducible manner. Surface enhanced Raman scattering (SERS) measurements are performed for different proteins, namely, lysozyme, ribonuclease-B, bovin serum albumin, ferritin, and myoglobin in the temperature range between -65°C and 90°C, using Device1, which is fabricated by means of e-beam and electro-plating technique. The calculation shows the possible detection of myoglobin concentration down to attomole. The in-depth analysis even for small conformational changes is performed using 2D Raman correlation analysis and difference Raman analysis in order to gain straightforward understanding of proteins undergoing thermodynamical perturbation. Device2 is fabricated by e-beam and metal electroless techniques to investigate the Rhodamine 6G (R6G) of different concentrations. Modifying this device by using bimetal (Ag and Au) electroless deposition permits us the further enhancement in Raman signal and better durability.