Photodynamic therapy (
PDT) is a promising noninvasive treatment modality for
cancer.
Photosensitizer and specific wave length of light are the key component of
PDT.
DH-I-180-3, a second generation
photosensitizer, was incorporated into
lipid nanoparticle for simultaneous fluorescent imaging and targeting
therapy. Solid
lipid nanoparticle (SLN) and nanostructured
lipid carriers (NLC) based on
poloxamer 188 as
surfactant and
lecithin as co-
surfactant were prepared using
solvent evaporation and hot homogenization technique.
Stearic acid and
Capmul(®) MCM C8 were utilized as solid
lipid and liquid
lipid, respectively. The particle size of SLN and NLCs was around 200 nm and decreased when a part of
stearic acid was replaced with
Capmul(®) MCM C8. Drug loading efficacy was significantly enhanced when the percentage amount of liquid
lipid increased. All the polydispersity indices of the SLN/NLCs were below 0.3, and displayed a narrow particle size distribution. Zeta potentials of all the
lipid nanoparticles were below -30 mV, maintaining sufficient repulsive force and achieving enhanced physical stability. No significant change in the particle size and polydispersity index was observed from lyophilized SLN/NLCs. When the photocytotoxic effects of the formulations were evaluated in MCF-7 cells, GI 50 of SLN was less than half of
DH-I-180-3 solution, and NLCs containing either 5 or 15%w/w of
Capmul(®) MCM C8 exerted higher cytotoxicity than SLN. The fluorescence microscope images displayed enhanced cellular accumulation of
DH-I-180-3 loaded in SLN and NLCs, which was closely correlated with the photocytotoxicity results. It was concluded that the incorporation of
DH-I-180-3 into the nanoparticles enhanced their targeting efficacy and improved photocytotoxicity.