Characterization of photobiophysical properties of sensitizers used in photodynamic therapy

摘要

Abstract: Tetrapyrroles obtain very good photophysical properties making them efficient photosensitizers in photodynamic therapy. Most of them have high triplet quantum yields, long triplet lifetimes and triplet state energies suitable for singlet oxygen generation. These photophysical parameters differ depending on the chemical structure and interactions with the environment. Today a large variety of tetrapyrroles are synthetized or chemically separated from natural substances for investigation of their photophysical properties with the aim of using them in photodynamic therapy. In this paper, some general aspects of energy conversion and energy transfer of tetrapyrroles in relation to their photophysical and biophysical properties relevant for photodynamic activity are discussed. Essential optical methods for the investigation of these parameters, as well as the determination of segmental mobilities of sensitizer-carrier complexes, are discussed using the example of phthalocyanines.!12