engleski

PDT potential of amphiphilic free-base and Zn(II) tripyridylporphyrins

Photodynamic therapy (PDT) is a treatment modality used for malignant diseases where the combination of light, photosensitizer (PS) and molecular oxygen produces reactive oxygen species (ROS), which leads to cytotoxic effect and tumour destruction [1]. Characteristics of a good PS include good absorption of light in the red region of the spectrum, stability, negligible dark toxicity, and good production of singlet oxygen [1]. Increased production of singlet oxygen can be achieved by chelation with paramagnetic metals, such as zinc(II), since they increase the lifetime of the PS’s triplet state (3PS*)[2]. Lipophilicity also plays an important role in effectiveness of a PS in PDT. Hydrophobic moieties in PS facilitate passing through the membrane lipid bilayer, however, they reduce solubility in water and tend to aggregate. Hydrophilic moieties, on the other side, impair membrane penetration and cell internalization [3]. In this work, we investigate free-base, and Zn(II) chelated, amphiphilic tripyridylporphyrins, conjugated with chains of various length. Physiochemical properties of the prepared porphyrins will be analysed and compared. The relationship between these properties and PDT activity of the compounds will be shown using cytotoxicity test.

Amphiphilic porphyrins ; Cytotoxicity ; Lipophilicity ; Singlet oxygen production ; Zn(II) chelation

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