Characterization of the thermalisation efficiency and photostability of photoacoustic contrast agents
نویسنده
چکیده
A simple method of characterizing organic dyes and nanoparticles used as contrast agents for photoacoustic molecular imaging based on relative photoacoustic measurements is described. By acquiring just two time-resolved photoacoustic signals, one in the sample of interest and the other in water, measurements of the thermalisation efficiency and other parameters relevant to the characterization of contrast agents can be acquired. The method was validated using absorbing solutions of known thermalisation efficiency and Grüneisen coefficient. It was then used to measure the thermalisation efficiency of solutions of gold nanorods, rhodamine B, methylene blue, IR-820, fluorescein and cresyl violet. In addition, photoacoustic measurements of the photostability of these substances were acquired.
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