Aptamer Nanoconjugates: New Tools for Molecular Imaging with Potential for Early Diagnosis of Pulmonary Emboli

Molecular imaging is an emerging field within science and medicine. This new technology will allow scientists and clinicians to visualize disease in a way previously unattainable. To advance this field, a new contrast agent is needed. Nanoparticles offer an ideal platform with the potential to fill this role. Not only are they proving to be useful as a general contrast agent but they can also be designed to target specific biomarkers. This is largely due to their inherent surface chemistry properties that allow us to conjugate them with targeting agents, such as aptamers. Aptamers are DNA, RNA, or XNA oligonucleotides selected to specifically bind proteins and other small molecules. Combining aptamer and nanoparticle allows for molecular targeting coupled to a highly sensitive detection capability. Recent investigation has shown the aptamer nanoconjugate platform to be useful as biosensors, in in vitro imaging of molecular/cellular events, and in in vitro/in vivo imaging of specific types of cancers. There are several research areas that remain to be studied, including but not limited to; image detection optimization, toxicity profiling, functionalization and aptamer surface interaction of nanoparticles. This technology has the potential to be extended to all areas of medicine and modern health problems. This review highlights one potential use, imaging of pulmonary emboli, which has been particularly challenging clinically. In this context, aptamer nanoconjugates offer a promising approach.