Mapping the formation of gemcitabine-immunoglobulin nanoparticles and the subsequent activity against pancreatic cancer cells

This research involved the synthesis of Gemcitabine-immunoglobulin nanoparticles (GIgG NPs) and the exploration of their apoptotic mechanisms in targeting Panc-1 cancer cells. A desolvation technique for synthesis was applied, resulting in the heterogeneous clustering of IgG molecules with several Gemcitabine molecules. The DLE and DEE were determined to be 6.8 +/- 0.32 % and 93.28 +/- 2.88 %, respectively. Dynamic Light Scattering (DLS) and imaging analysis indicated a size of 122.1 nm, a PDI of 0.21, and a zeta potential of-23.78 mV. Fluorescence spectroscopy revealed a reduction and shift in the intrinsic fluorescence of IgG as the Gemcitabine concentration increased. ITC data showed that the binding sites (n) for IgG were 0.96, suggesting roughly one Gemcitabine binding site per IgG molecule, while for GIgG NPs, the n value was measured at 0.84. The binding constant (Kb) for IgG-Gemcitabine was 2.06 x 105 M- 1, while for GIgG NPs, it was 1.26 x 105 M- 1. The Gibbs free energy (Delta G degrees) for IgG-Gemcitabine was-30.41 kJ/mol, while for GIgG NPs it was-29.18 kJ/mol. Moreover, negative Delta H degrees and positive Delta S degrees values suggested that hydrogen bonds and hydrophobic interactions could facilitate the formation of the complex. Molecular docking analysis indicated that nonpolar interactions and intermolecular solvation play a role in the binding of Gemcitabine to IgG. The release kinetics aligned closely with the Korsmeyer-Peppas and Higuchi models for the pH-sensitive release of Gemcitabine. The IC50 of Gemcitabine for Panc-1 cancer cells dropped seven-fold when encapsulated in GIgG NPs, demonstrating enhanced cytotoxicity and selective targeting of cancer cells. Mechanisms for inducing apoptosis were evident via increased effectiveness, gene expression alteration, caspase activation, and oxidative stress. These results indicate that GIgG NPs could serve as a potential therapeutic option for the targeted treatment of pancreatic cancer.