Multispectral analysis of photoacoustic signal for improvement in identification accuracy of imaging probe

抄録

In order to establish deeply penetrating photoacoustic cancer imaging technology, we are designing and synthesizing photoacoustic probes and developing imaging technology of the probes. Both small organic molecule- and plasmonic gold nanoparticle-based probes are studied as photoacoustic probes. As photoacoustic imaging provides a spatial distribution of photon absorber, intrinsic photon absorber such as hemoglobin becomes a strong background in the case of visualizing the probe signal selectively. Thus, a method to extract the probe signal from the background signal has been required. We applied multispectral unmixing method to the photoacoustic data to identify the probe of distinct optical absorption spectrum. The multispectral photoacoustic measurements of activatable rhodamine probes as small organic molecules, and various plasmonic gold nanoparticles were performed using a tunable laser. Accordingly, there is high probability that the multispectral unmixing method enables us to visualize accurate distribution of the photoacoustic probe.