Enl. Chan et Dm. Goodall, CAPILLARY ELECTROPHORESIS ANALYSIS OF POLYHEMATOPORPHYRIN, A PHOTOSENSITIZER USED IN PHOTODYNAMIC THERAPY, Journal of chromatography, 636(1), 1993, pp. 171-178
Free solution capillary electrophoresis and micellar electrokinetic ca
pillary chromatography are used to separate components in polyhaematop
orphyrin (PHP), a preparation similar to Photofrin which is used as a
photosensitizing agent in photodynamic therapy. PHP is known to contai
n haematoporphyrin (HP), protoporphyrin (PP), hydroxyethylvinyldeutero
porphyrin (HVD) and a mixture of ester, ether and carbon-carbon linked
oligomers. The use of reference samples of HP and PP, together with p
artially dehydrated HP, has allowed assignment of HP and HVD peaks in
the electropherograms of PHP in 20 mM phosphate pH 6.9 and 20 mM disod
ium tetraborate pH 9.2 buffers using sodium dodecyl sulphate in the ra
nge 0-100 mM. Changes in the pattern and areas of monomer peaks and ol
igomer distribution following base hydrolysis (which cleaves ester lin
kages) and acid hydrolysis (which cleaves ester and ether linkages) yi
elds information consistent with that from HPLC studies.