Harnessing Cationic Bilosomes to Create a Green Light-Triggered Nanoplatform for Skin Melanoma Treatment.

Abstract

Background: Vesicular drug delivery systems, including bilosome-based nanoparticles containing bile salts, have revolutionized the field of colloid chemistry, nanomedicine, and nanobiotechnology. Due to their versatility and adaptability to various applications, they have gained considerable attention among researchers, thus offering a promising pathway to achieve effective and targeted delivery of miscellaneous drugs.

Purpose: This study presents a novel class of positively charged bilosomes with surface-associated poly(ethylene glycol) (PEG)-lipid, co-entrapped the anionic xanthene dye (Rose Bengal), and natural carotenoid pigment derived from the mold Blakeslea trispora (astaxanthin), as a safe and effective transdermal drug delivery system.

Methods: Bilosomal nanosystems were prepared using thin film hydration combined with sonication. The physicochemical properties of the vesicles were characterized, including particle size, zeta potential, entrapment efficiency, and morphology. Cellular uptake, cyto- and phototoxicity experiments were investigated in vitro against human melanoma cancer cells.

Results: The multidrug bilosome formulation exhibited a particle size of less than 100 nm and a zeta potential of more than +40 mV, indicating beneficial properties for potential transdermal administration. In vitro biological experiments have shown remarkable antitumor efficacy against human skin epithelial (A375) and malignant (Me45) melanoma cell lines. After irradiating the samples with green light at a wavelength of 520-560 nm (10 J/cm² of total light dose), we observed a significant decrease in mitochondrial metabolic activity, ie, a reduction in cell viability below 30% compared to the control. Higher phototherapeutic activity, in contrast to the administration of non-encapsulated active agents, indicates shared synergistic effects through the simultaneous action of advanced bilosome-derived nanophotosensitizers and phyto-photodynamic therapy.

Conclusion: Our encouraging results provide new potential candidates for preclinical development in innovative photodynamic therapy targeting melanoma and also pave the way for future therapeutic strategies with broad applications in many biological fields.