The present invention provides soluble single wall nanotube (SWNT) constructs functionalized with a plurality of a targeting moiety and a plurality of one or more payload molecules attached thereto. The targeting moiety and the payload molecules may be attached to the soluble SWNT via a DNA or other oligomer platform attached to the SWNT. These soluble SWNT constructs may comprise a radionuclide or contrast agent and as such are effective as diagnostic and therapeutic agents. Methods provided herein are to diagnosing or locating a cancer, treating a cancer, eliciting an immune response against a cancer or delivering an anticancer drug in situ via an enzymatic nanofactory using the soluble SWNT constructs.