2:30 PM - 2:45 PM
▲ [15p-C31-3] Analysis of Raman Spectra Measured in Dynamic SERS Imaging of Intracellular Transport
Keywords:Raman scattering, SERS, metal nanoparticles
Raman scattering represents the information of analyte molecules through scattering light with characteristic vibrational wavelength. Since this phenomenon is rarely occurred, biological activities occurring in short time is difficult to observe. Raman scattering can be enhanced with using metal nanoparticles. Molecules existing nearby or adsorbed on the metal nanoparticles make Raman scattering stronger due to the locally enhanced electric field around the metal nanoparticles (surface-enhanced Raman scattering; SERS). SERS enables us to observe biomolecules in short time associated with biological events. Here, we present the method of observing intracellular transportation by using SERS from metal nanoparticle. The metal nanoparticle works as a prove for observing biomolecules and an agent for SERS. Living cells uptake the metal nanoparticles through endocytosis process. The nanoparticles moves along with transportation system. We developed a three-dimensional nanoparticle tracking system and combined with a confocal Raman microscope. A laser beam was focused on the target nanoparticles and it resulted in providing SERS during the intracellular transportation every 100 ms. We analyzed time-series Raman spectra, considering both the motion of the nanoparticle and time. Principal component analysis (PCA) and cross correlation analysis revealed that some molecular vibrational modes showed strong correlation with the metal nanoparticle motion. This analysis taking into account of time-space-spectrum enable us to visualize the molecular interaction of the events inside a cell.