Photoacoustic Spectroscopy—Leaf Absorption Spectra

Abstract

Using a relatively recent technique, photoacoustic spectroscopy (PAS), purple pigmentation in leaves of three species of Euphorbia was characterized as anthocyanin by observing a peak at 545 nm. The in vivo chlorophylls of the leaf have a recorded maximum absorption peak at 675 nm as against 665 nm of the in vitro chlorophylls. The intensity of purple pigmentation in leaves of Euphorbia hirta L., are inversely correlated to the soil moisture levels, leaf water content and leaf water potentials. The applicability of PAS to biological samples was discussed.