<b>Development and Characterization of Liposomal Phytoformulation of <i>Piper longum</i> L. for Melanoma Therapy</b>

Background: Melanoma is a highly destructive and lethal form of skin cancer. With the contemplation of the concept of plant-based chemotherapeutic and nanomedicine approach, this study aims to develop a liposome of standardized Piper longum L. fruit ethanolic extract (PLFEE), with the evaluation of its pharmaceutical properties and cytotoxic activities against melanoma cell line. To our knowledge, no authentic reports are available for the standardized PLFEE-loaded liposome for melanoma therapy. Methods: The chemical marker-based standardization of PLFEE was performed by validated High-performance liquid chromatography (HPLC) to maintain the dosage uniformity and uniform therapeutic outcome. Thin-film hydration was utilized for the formulation of liposomes. The developed liposome was characterized for its pharmaceutical possessions and therapeutic activity against melanoma cell lines. Results: The prepared liposome was found to be homogeneous, amorphous, transparent, light yellowish, demonstrated nano vesicular size (Zavg=104.858±0.262 nm), low polydispersity index (PDI=0.271±0.015), high zeta potential (ζ= -21.8±0.07 mV), spherical morphology, excellent % entrapment efficiency (EE=75.920±3.096%), refractive index (RI= 1.335±0.0001), sustained drug release, excellent drug-excipient compatibility, and stability. The liposome showed selective cytotoxicity to B16F10 melanoma cells without affecting healthy HEK293 kidney cells. The PLFEE-loaded liposome showed significantly enhanced cytotoxicity (IC50=59.71 ± 2.364 µg/mL) compared to PLFEE (88.48 ± 3.243 μg/mL). Conclusion: Cancer cells use various pathways for their uncontrolled, abnormal proliferation, angiogenesis, invasion, and metastasis. It is, therefore, logical to utilize a multicomponent-based standardized herbal extract that may act through multiple molecular pathways. The liposomal formulation containing multiconstituent-based standardized PLFEE may be a potential alternative chemotherapeutic for melanoma therapy. However, comprehensive in-vivo works are essential to reveal its therapeutic potential.