LIPID-BASED NANOCARRIERS IMPROVED ZnPcSO4 CELLULAR UPTAKE IN HUMAN KERATINOCYTES FOR USE IN TOPICAL PHOTODYNAMIC THERAPY

Topical photodynamic therapy (PDT) involves both local administration of a photosensitizing drug followed by illumination or irradiation of visible light, resulting in light-drug combinations to kill cells and microorganisms.  PDT using tetra-sulfonate phthalocyanine, a second generation of hydrophilic photosensitizers, has recently become a good treatment option for treatment of skin malignances. However, tetra-sulfonate phthalocyanine must be delivered into the target layers of the skin to achieve promising results. Thus, strategies to improve the phthalocyanine cell uptake based on lipid-based nanocarriers were evaluated in this work. The results showed that tetra-sulfonate phthalocyanine loaded lipid-based nanocarriers (microemulsion and liquid crystalline nanodispersion) have nanometric particle size, with low polydispersity,  negative zeta potential and high ZnPcSO4 encapsulation efficiency. Furthermore, both nanocarriers  investigated presented little cytotoxicity against HaCaT cells, however the microemulsion presented higher toxicity upon higher concentrations. Finally, the formulations developed herein enabled high ZnPcSO4 uptake, a promising result. Future studies will be conducted using tumor skin cells lines.