Nanoparticles can be useful for delivering therapeutic agents, such as anticancer agents to diseased cells. The nanoparticles include a carrier polypeptide and a cargo, which can be bind through electrostatic interactions to form a nanoparticle composition. An exemplary composition comprises nanoparticles comprising a carrier polypeptide comprising a penton base segment and a binding segment: and a polypeptide cargo comprising a tag segment that binds to the binding segment of the carrier poly peptide through an electrostatic interaction. An exemplary carrier polypeptide comprises a penton base segment and a negatively -charged binding segment, which can bind to a positively charged cargo. The carrier polypeptide can also include a cell-targeting segment which can target the nanoparticle to a cell. Compositions comprising nanoparticles can be administered to a subject for the treatment of disease, such as cancer.
