Formation of metal complexes of tumor‐localizing porphyrins

Abstract

Whereas the tumor localizer and photosensitizer hematoporphyrin derivative (Hpd) has its fluorescence emission maximum at 610-630nm, several authors have reported that in aqueous solutions of hematoporphyrin (Hp) and Hpd, or in tumors after an injection of Hpd, a compound is formed which has its fluorescence emission maximum at 570-590nm.This work (HPLC and fluorescence analysis) indicates that this peak is due to the formation of Zn-porphyrins either in vitro or in vivo. Cu-and Co-porphyrins may be formed as well, from traces of these metallic ions. In contrast to free porphyrins and Zn-porphyrins the latter complexes are non-fluorescent and do not act as photosensitizers. Metalloporphyrin Tumor localizer Fluorescence Photosensitizer ChromatographyPhotochemotherapy

The Photochemistry of Haematoporphyrin and Related Systems

“…However, Sommer et al (1984) have presented HPLC, absorbance and fluorescence data that supports the assignment of this new 580 nm band as being due to a zinc haematoporphyrin complex. This is discussed later with respect to fluorescence lifetimes.…”

Different modes of DNA cleavage activity of dihydroxo-bridged dicopper(II) complexes having phenanthroline bases

“…The dpq and dppz complexes show efficient photo-induced DNA cleavage on red light irradiation, while the ligands alone are cleavage inactive. The results are of importance as the copper-porphyrin complexes are known to show less efficient photo-cleavage in comparison to the porphyrin base [14][15][16].…”

Photodynamic therapy and diagnostic measurements of basal cell carcinomas using esterified and non-esterified δ-aminolevulinic acid

“…The autofluorescence in that interval was fitted by the least-square method and extrapolated to 635 nm. Small intervals in this spectral range were occasionally omitted to prevent endogenous porphyrin peaks, at about 580 nm, from affecting the fit [14]. To make a qualitative assumption of the differences between ALA and ALA-ME, the ratio between the PpIX peak (at 635 nm after subtraction of the extrapolated autofluorescence) and the autofluorescence maximum was calculated and evaluated.…”