[5p-A409-1~11] 4.2 Bio-and Medical Photonics

▼ [5p-A409-7] Observation of nonlinear scattering from gold nanoshells

〇(M2)Kentaro Nishida¹, Gitanjal Deka², Nicholas Smith¹, Shi-Wei Chu², Katsumasa Fujita¹ (1.Osaka Univ., 2.Ntl. Taiwan Univ.)

Keywords:Supur resolution, Plasmon, Nonlinear

Optical microscopy has the capability of observing the inside of a biological tissues. However, the contrast of an image can be significantly degraded with the increase of the observation depth is increased. This is because the signal light is attenuated during passing through the tissue layers. To obtain a high contrast image even from a deep part of a tissue, we proposed to apply saturated excitation (SAX) microscopy using near infrared plasmonic scattering of gold nanoshells. Saturated excitation microscopy selectively detects the nonlinear scattering signal from metallic nanoparticle probes and shows the improved spatial resolution. By using this technique, the background light from a tissue is effectively reduced since it does not show the nonlinear relations with the excitation light. In addition, near infrared signal light can penetrate a biological tissue with reduced scattering and improve the throughput of signal detection. These unique properties of SAX microscopy are beneficial to improve the contrast especially in imaging a deep part of biological tissues. We experimentally confirmed that scattering of NIR light by a gold nanoshell shows the saturation effect and can be used to improve both spatial resolution and depth imaging capability.