Gold-nanoshells as surface plasmon resonance (SPR)

Coreshell plasmonic nanoparticles (CS) are a class of nanoparticles that exhibit optical absorption in the near IR regime and have potential biomedical applications in imaging, therapy and sensing. We present our preliminary investigation on the applications of CS as a surface plasmon based sensor to study the functional properties of human blood. CS particles of size about 1 mu m exhibit broad absorption between 650 nm to 1000 nm, the regime generally used to study blood saturation. We synthesized CS particles of size about 1 mu m, coated with a thin shell. The core medium was polystyrene and the nano-shell layer was gold. The plasmon peak of CS varied with blood concentration. The study showed that 750 nm plasmonic peak of CS exhibits the wavelength shift of 4.11 +/- 0.26 nm per hematocrit.