Effect of curcumin-loaded poly(amidoamine) dendrimer on cancer cell lines: a comparison between physical loading and chemical conjugation of drug

Curcumin, an anti-cancer compound found in the spice turmeric, is difficult to use because of its low water solubility. Poly(amidoamine) dendrimers are macromolecules with many nanoscale branches and extremely active amine groups on their surfaces, allowing them to attach to anticancer medicines such as curcumin. The goal of this study was to synthesize and evaluate the structural and anti-cancer properties of the poly(amidoamine)-curcumin dendrimer complex. Poly(amidoamine) dendrimer was synthesized up to the fourth generation (G4) and modified with glycidol to form the hydroxyl terminated dendrimer (G4–OH). Then, folic acid (FA) was utilized as a ligand to target the system specifically for cancer cell penetration. In addition to the physical loading of curcumin (Cu) on the FA-grafted dendrimer (G4–FA), curcumin was modified using ethyl bromoacetate, hydrolyzed with sodium hydroxide, and prepared to attach chemically to the hydroxyl terminated dendrimer (G4–Cu). FT-IR and ¹H-NMR characterizations showed successful synthesis of the dendrimers as well as attachment of modified curcumin on the G4 surface. G4–FA revealed more effective performance in the release of loaded curcumin with release of 63.7% of loaded drug during 12 h. Using two cell lines of MG-63 and HT-29, the G4–Cu complex had the greatest growth inhibitory effect by increasing time among the derivatives, with the cell viability rate dropping by about 67%. These findings suggest that curcumin in combination with a fourth-generation dendrimer could be an effective cancer-fighting agent. The G4–Cu causes the complex to work more effectively, killing cancer cells to a greater extent, indicating the potential of the poly(amidoamine) dendrimer derivative for cancer treatments.