A Hybrid Plasmonic Bimetallic Nanoshell-Microsphere Sensor for Cancer Market Protein Detection

• Published in: Plasmonics (Norwell, Mass.) Mass.), 2017-12, Vol.12 (6), p.1953-1960
• Main Authors: Garaei, Marzieh Afkhami, Saliminasab, Maryam, Nadgaran, Hamid, Moradian, Rostam
• Format: Article
• Language: English
• Subjects: Bimetals; Biochemistry; Biological and Medical Physics; Biophysics; Biotechnology; Cancer; Chemistry; Chemistry and Materials Science; Electric fields; Markets; Nanotechnology; Optical properties; Raman spectra; Resonance scattering
• ISSN: 1557-1955; 1557-1963
• DOI: 10.1007/s11468-016-0467-z

In this paper, the detection of a thyroid cancer market (Thyroglobulin, Tg) protein has demonstrated by using a hybrid plasmonic bimetallic nanoshell-microsphere sensor based on the reactive sensing principal (RSP). Tunable optical properties and plasmon resonances at three frequencies made a bimetallic nanoshell more special for sensing purposes. The rough surface of the bimetallic nanoshell affixed to the microsphere surface locally enhanced the electric field within the microcavity without significantly degrading a Q-factor (~ 7.59 × 10 5 ), at near infrared wavelength. The rough surface of the bimetallic nanoshell effectively enhanced a wavelength shift of the hybrid microcavity by the factor of ~300. At lower energy mode, the electric field enhancement of the hybrid plasmonic microsphere resonator increases by ~863% at the surface of the bump in comparison with a smooth nanoshell. This enhancement occurs in rough bimetallic nanoshell as localized surface Plasmon resonance (LSPR), which increases the Raman signal through the surface Raman scattering (SERS) effect in hybrid microcavity. Calculated results demonstrate that the hybrid plasmonic microsphere resonator can generate very strong SERS enhancement factor at a visible wavelength (~1.5 × 10 7 ).