At present, most researches use the frequency and amplitude of photoacoustic effect to obtain target information. As we know, the spectrum of sound can reflect some properties of the generator. However, existing photoacoustic imaging mainly relies on light absorption properties as molecular fingerprints of contrast agents. Why not use the spectrum of sound as a molecular fingerprint? Looking forward to your reply, many thanks!
Photoacoustic signals generated by photoacoustic contrast agents are generally very broadband (the 'N'-wave is very short in time) due to their small size (nm). It is affected, during propagation, by tissue frequency dependant attenuation (which would include tissue scattering), and diffraction associated with the transducer receive aperture, which would need to be compensated for. Added to these, the centre frequency and bandwidth of the receive transducer itself, would limit both the resolution and, drastically, the frequency range of analysis. For all these reasons, acoustic spectral analysis would be insensitive to the nature of the contrast agent. This is why "molecular fingerprinting" is done on transmit, based on the interaction with light, and not on receive (based on the generated acoustic signal).
- Badges
- Science topic
- Similar topics
- Filing