Imprint Lithography-Based, Multimodal Contrast Agents and the Effect of Shape and Size on Biodistribution
K.P. Herlihy, T.J. Merkel, J.M. DeSimone
UNC Chapel Hill, US
Keywords: nanoparticle, MRI, PET, biodistribution, Imprint Lithography
Abstract:Polymer research and modern medicine are at a critical juncture. Many state of the art, small molecule therapeutics are difficult to deliver effectively because of poor solubility and rapid elimination by the reticuloendothelial system. In addition, many old therapies are in need of repackaging. As a result, researchers are turning to alternative methods for delivery of a wide range of therapeutics. Herein we employ a top-down particle fabrication technique called Particle Replication In Non-wetting Templates (PRINT®) to fabricate unique biocompatible particles with distinct therapeutic properties based on their composition, size, shape and cargo. The particles are easily tagged with a variety of imaging beacons and radioisotopes making them effective as contrast agents for magnetic resonance imaging, positron emission tomography and fluorescence imaging and as radiotherapeutics. Using the PRINT® technique, we are able to design particles that will target or de-target specific organs and tissues as a function of their size and shape. To our knowledge this work represents the first example of imprint lithography-based multimodal contrast agents and the first in-depth study of biodistribution of nanometer scale shape and size specific particles.