The present invention provides nonradioactive NIR optical imaging agents based up on the structure of retinoid acid derivatives. The nonradioactive NIR optical imaging agent has been evaluated at the cellular level by confocal microscopy, and in vivo in a whole animal using a various xenograft models. The specific uptake of this agent in human cancer cells and multiple xenograft models demonstrate that nonradioactive near infrared dye labeled retinoid metabolites and/or analogs are useful for early stage cancer studies and diagnoses. Also, the present invention provides that nonradioactive near infrared dye labeled retinoid metabolites and/or analogs are useful for visualization of drug redistribution within the body which is useful in determining the optimal biological dose. Ultimately, the visualization data can be used as an analytical tool to reduce any systemic toxicity.
