Preparation and Characterization of PEGylated Liposomal Doxorubicin Targeted Formulation for Colon Carcinoma

Colon carcinoma remains a major global health concern, necessitating the development of advanced drug delivery systems to enhance therapeutic efficacy while minimizing systemic toxicity. This study focuses on the preparation and characterization of PEGylated Liposomal Doxorubicin (PLD) targeted formulation for colon carcinoma treatment. PEGylated liposomes were formulated using the thin-film hydration method, followed by extrusion for size uniformity. The formulations were characterized for particle size, zeta potential, encapsulation efficiency, morphological attributes, in vitro drug release kinetics, and stability studies over 90 days. The mean particle size ranged from 85 to 145 nm, with an optimal zeta potential ensuring colloidal stability. Encapsulation efficiency exceeded 85%, confirming effective drug entrapment. Morphological analysis using TEM and SEM revealed spherical, uniform vesicles with a smooth lipid bilayer, with PEGylation significantly enhancing vesicle stability. In vitro drug release studies demonstrated a sustained release profile, with F3, F4, and F5 best fitting the Korsmeyer-Peppas model (R² > 0.98), indicating a non-Fickian diffusion mechanism. MTT assay on HT-29 cells confirmed superior cytotoxicity of PLD compared to free doxorubicin, with a lower IC₅₀ value. Stability testing at 4°C and 25°C for 90 days confirmed formulation integrity, with negligible degradation. These findings suggest that PEGylated liposomal doxorubicin exhibits enhanced stability, controlled drug release, and targeted cytotoxicity, making it a promising candidate for colon carcinoma therapy. Further in vivo studies are warranted to validate its clinical potential.