Scattering photoacoustic study of weakly-absorbing substances in aqueous suspensions

This study explores the application of the scattering photoacoustic (SPA) technique to the study of weakly-absorbing substances in suspensions. The technique allows the scattering and PA properties of weakly absorbing materials to be examined simultaneously. The experiment reported here measured the reduced scattering coefficients of milk, intralipid and polystyrene suspensions with and without glucose. It turned out that in milk the SPA method has a higher detection sensitivity for fat than for glucose. Nonetheless, glucose was observed to have a larger effect on scattering in light milk and intralipid-1% bases than in non-fat milk and polystyrene-0.5% bases, although the scattering effect contributed little to the PA signal produced in the suspensions.