Wavelength dependence and kinetics of the photovoltaic effects
in chloroplast suspensions

Geza Meszena

Biophysical Chemistry 48: 315-319 (1994)

Summary

The photovoltaic effect in chloroplast suspension is studied
using laser pulses of various wavelengths in a single
experimental setup. The polarity of the photovoltage depends on
the wavelength of the laser pulse rather than the differences
between laser and flash-lamp pulses. At the long-wavelength-side
of the visible spectrum and between the two absorption bands of
the chlorophyll the observed polarity is opposite to that
expected from simple shading. Also, the decay kinetics of the
signals are wavelength dependent. In some wavelength regions the
signal has a positive, as well as a negative component. We show
that swollen chloroplasts exhibit understandably different
photovoltaic effects. This observation suggests, that polarity
depends on the geometry of the chloroplasts and support the
theory, that the interference pattern of the light distribution
determines the polarity of the signal.