Cancer and
drug-resistant
superinfections are common and serious problems afflicting millions worldwide.
Photodynamic therapy (
PDT) is a successful and clinically approved modality used for the management of many neoplastic and nonmalignant diseases. The combination of the light-activated molecules, so-called
photosensitizers (PSs), with an appropriate carrier, is proved to enhance
PDT efficacy both in vitro and in vivo. In this paper, we focus on the solvation of several potential
chlorin PSs in the
1-octanol/
phosphate saline
buffer biphasic system, their interaction with non-ionic
surfactant Tween 80 and photoinactivation of
cancer cells. The
chlorin conjugates containing
d-galactose and
l-arginine fragments are found to have a much stronger affinity towards a
lipid-like environment compared to ionic chlorins and form molecular complexes with
Tween 80 micelles in water with two modes of binding. The charged macrocyclic PSs are located in the periphery of
surfactant micelles near hydrophilic head groups, whereas the
d-galactose and
l-arginine conjugates are deeper incorporated into the
micelle structure occupying positions around the first
carbon atoms of the hydrophobic
surfactant residue. Our results indicate that both PSs have a pronounced affinity toward the
lipid-like environment, leading to their preferential binding to
low-density lipoproteins. This and the conjugation of
chlorin e6 with the
tumor-targeting molecules are found to enhance their accumulation in
cancer cells and
PDT efficacy.