Embodiments of the present disclosure provide for water soluble polyethylene glycol (PEG)-polymeric melanin (PEG-melanin) nanoparticles, methods of using the PEG-melanin nanoparticle, methods of making the PEG-melanin nanoparticle, methods of imaging a diseases or condition (e.g., pre-cancerous tissue, cancer, or a tumor), and the like. Embodiments of the present disclosure can be used in multimodal imaging (e.g., photoacoustic, nuclear, magnetic, fluorescent, and the like).
