F. Ricchelli, PHOTOPHYSICAL PROPERTIES OF PORPHYRINS IN BIOLOGICAL-MEMBRANES, Journal of photochemistry and photobiology.B, Biology, 29(2-3), 1995, pp. 109-118
This review illustrates the photophysical properties of some porphyrin
s, especially those used for biomedical applications, in relation to t
heir photosensitizing efficiency in biological membranes. Porphyrin ab
sorption and luminescence properties are mainly examined. The factors
influencing the affinity of porphyrins for biological membranes, inclu
ding the dye hydrophobicity, the charge and aggregation state, the pH
of the medium and the physicochemical properties of the dye environmen
t, are discussed. These factors determine the differences in the photo
physical properties of porphyrins in biological membranes. Particular
attention is paid to the porphyrin aggregation state: only monomeric s
pecies and possibly planar end-to-end aggregates are endowed with sign
ificant photosensitizing ability. Many conclusions presented are based
on data obtained on membrane model systems such as micelles or liposo
mes which can mimic specific situations occurring in cells.