09:30 〜 09:45
▲ [14a-2C-2] Targeted intracellular detection of cellular components by in-situ fabrication of plasmonic Raman probes
キーワード：intracellular plasmonic enhancement,enhanced biological spectroscopy,in-situ nanofabrication
The use of plasmonic enhancement has provided highly sensitive molecular discrimination in samples of sizes down to even several nanometers. A variety of clever plasmonic techniques have been developed, but many of these are not relevant for biological samples. In particular, intracellular plasmonic measurements remain challenging. This is due to the fact that the most simple plasmonic device that might enter a cell is a nanoparticle or nanoparticle aggregate. After entering the cell, these are usually not under the control of the observer, and end up in accumulated spaces in the cell. There they are still useful as enhanced probes of cellular transport pathways, but without some method of controlling the type and location of nanoparticles, the type of experiments that can employ intracellular plasmonics is limited.
Here we present an all-optical method of gold nanoparticle fabrication inside the cell, where a precursor gold ion solution is first infused through the cell, then several milliwatts of tightly-focused irradiation from a 532 nm cw beam can form single-crystal gold nanoparticles inside the cell. The particles remain at the location of the irradiation, forming an aggregate which is approximately confined to the laser focal region. A second irradiation by a longer wavelength beam (780 nm) can then excite the plasmon resonance and enhance the molecular Raman signal from the local region or hotspots near the particles. The resulting spectra show that the technique can fabricate plasmonic Raman probes in any location inside the cell, and provide spectra from the cellular interior. Interestingly, even with the ability to control particle formation, the detected SERS spectra are not exhibited at all nanoparticle locations, and the use of an algorithmic approach to study the detected spectra complexity in a non-biased framework is very useful.
Here we present an all-optical method of gold nanoparticle fabrication inside the cell, where a precursor gold ion solution is first infused through the cell, then several milliwatts of tightly-focused irradiation from a 532 nm cw beam can form single-crystal gold nanoparticles inside the cell. The particles remain at the location of the irradiation, forming an aggregate which is approximately confined to the laser focal region. A second irradiation by a longer wavelength beam (780 nm) can then excite the plasmon resonance and enhance the molecular Raman signal from the local region or hotspots near the particles. The resulting spectra show that the technique can fabricate plasmonic Raman probes in any location inside the cell, and provide spectra from the cellular interior. Interestingly, even with the ability to control particle formation, the detected SERS spectra are not exhibited at all nanoparticle locations, and the use of an algorithmic approach to study the detected spectra complexity in a non-biased framework is very useful.