Preparation and Evaluation of Folic Acid-Modified Gambogic Acid Nanocrystals-Phospholipid Composite Drug Delivery System

• • GA-NCs@PL-FA achieved an encapsulation efficiency of 84.64 ± 0.57% and drug loading of 4.33 ± 0.07%, with a particle size of 183.07 ± 0.55 nm and zeta potential of −17.70 ± 0.17 mV. These metrics indicate a physically stable colloidal system suitable for intravenous administration, with high drug-to-carrier ratio reducing excipient burden. • • The formulation exhibited sustained release in pH 7.4 and 6.5 PBS containing 0.5% Tween 80, with release profiles comparable to the non-folate version (GA-NCs@PL), confirming that folate modification via DSPE-PEG2000-FA does not compromise the lipid layer integrity. This is critical for maintaining consistent pharmacokinetics and avoiding burst release. • • In HepG2 cells, GA-NCs@PL-FA reduced the IC50 to 0.50 μg/mL, demonstrating superior anti-proliferative and anti-migratory activity versus free GA, GA-NCs, and GA-NCs@PL. This ~2-fold improvement over non-targeted counterparts underscores the active targeting benefit of folate receptor-mediated endocytosis. • • UPLC-MS/MS tissue distribution in tumor-bearing nude mice showed prolonged systemic retention and enhanced tumor accumulation of GA-NCs@PL-FA, with direct quantification of gambogic acid in tissues. This confirms that the nanocrystal-phospholipid composite with folate decoration synergistically improves tumor selectivity, potentially reducing off-target toxicity and improving therapeutic index.