Encapsulation of acetylshikonin by polyamidoamine dendrimers for preparing prominent nanoparticles

Acetylshikonin (AS) has demonstrated antitumor potential. However, the development of therapeutic applications utilizing AS is inhibited by its poor solubility in water. In the present work, polyamidoamine (PAMAM) dendrimers and their PEGylated derivatives were employed to increase the solubility of AS. A distinct color transition was observed during the encapsulation of AS suggesting strong intermolecular forces between PAMAM and AS. Ultraviolet-visible, high-performance liquid chromatography, and (1)H NMR were used to verify the interaction between PAMAM and AS. The maximum amount of combined AS to each PAMAM molecule was determined. The cytotoxicity of AS nanoparticles was evaluated against leukemia (K562) and breast cancer (SK-BR-3) cell lines; the AS nanoparticles were shown to effectively inhibit tumor cells.