“Plasmon Resonant Structures as Optical Contrast Agents”
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Abstract: Non-invasive optical imaging techniques play a critical role in modern medicine.  Further advancements of technology in this area improve the ability of clinicians to properly diagnose and recognize the early stages of progressive disease.  Contrast agents aid this process by providing images with more information.

Plasmon resonant nanoparticles can be designed or engineered to enhance several optical tissue interrogation methods including OCT, and 2-photon microscopy.   By varying parameters during synthesis, the extinction characteristics of nanoparticle suspensions can be tuned, resulting in the ability to match source wavelengths.  In tandem with dual-source imaging processes, further contrast enhancement can be realized through differential imaging utilizing narrow resonance bands of nanorods. Inert metal and phospholipid scaffolds were combined as gold-coated liposomes to form a contrast agent that not only serves its role in imaging, but also can be metabolized and cleared from the body.  Other uses of these materials are being investigated including the ability to carry fluorescent dyes, and use as photodynamic therapy agents to mediate light-induced ablation or release of compounds.