Haematoporphyrin derivatives: distribution in a living organism.

Pharmacokinetics of accumulation in organs and tissues was studied for two haematoporphyrin-based photosensitizers. These sensitizers, haematoporphyrin derivative (HpD) and an oligomeric haematoporphyrin (OHp), contained different amounts of monomeric fraction (25% and 5% respectively) and in OHp the macrocycles were bonded together with ether bonds. OHp was shown to accumulate in tumours in higher amounts than HpD.