Abstract
Enabled by their size and supramolecular structures, nanoparticles (that is, particles of approximately 10 to 100 nanometers) promise to be particularly capable agents in the detection, diagnosis, and treatment of cancer. When loaded with chemotherapeutic agents, nanoparticle delivery to cancerous tissues relative to healthy tissues may be favorably biased by size and through the attachment of targeting ligands to the surface of the particle. Nanoparticles may be made from a variety of materials, and in addition to chemotherapeutic payloads, nanoparticles can incorporate non‐bioactive elements useful as diagnostic and device agents. For example, the inclusion of iron oxide colloids enables nanoparticle use as magnetic resonance imaging (MRI) contrast agents, and also, through the application of an alternating magnetic field (AMF), enables the particle to generate enough heat to be used for hyperthermic therapeutic applications. In this report, we also introduce novel Magnetic Nanoparticle Hydro‐Gel (MagNaGel^TM^) materials comprised of chemotherapeutic agents, iron oxide colloids, and targeting ligands. MagNaGel particles were fabricated in the 20‐ to 40‐nm size range with very narrow size dispersion. These particles demonstrate high (>10 wt %) chemotherapeutic loading, tumor‐associated biomolecular binding, good magnetic susceptibility, and attractive toxicity and circulation profiles in mouse models. Looking forward, the convergence of drug and device on the nano‐scale promises treatment modalities that cannot be practiced through traditionally distinct drug and device combinations. MagNaGel nanoparticles are drug‐device hybrids that, when used in conjunction with diagnostic MRI and inductive heating, may play a key role in new and powerful cancer treatment regimens. Drug Dev. Res. 67:70–93, 2006. © 2006 Wiley‐Liss, Inc.