Characterization of plasmon-resonant gold nanorods as near-infrared optical contrast agents investigated using a double-integrating sphere system

Enhanced detection of early-stage oral cancer in vivo by optical coherence tomography using multimodal delivery of gold nanoparticles

“…A 71-nm-diameter Au NP (highly scattering dominant) was used as the OCT contrast agent because OCT detects backscattering signals from a sample 49. All glassware was cleaned in aqua regia (three parts HCl, one part HNO 3 ), rinsed with deionized water, and then dried prior to use.…”

Gold Nanomaterials at Work in Biomedicine

“…367,368 The DIS-IAD approach only requires a small amount of sample and can handle conditions where absorption is strong. A DIS apparatus contains two integrating spherical chambers with a thin slide of sample sandwiched between them.…”

Polypyrrole Nanoparticles: A Potential Optical Coherence Tomography Contrast Agent for Cancer Imaging

“…Gold nanoshells,11 gold nanoparticles,12 and iron oxide nanoparticles13 improve OCT image contrast by increasing the backscattered signal intensity. Alternatively, absorbing contrast agents, such as indocyanine green,14, 15 gold nanorods,16–18 gold nanocages,19, 20 gold‐coated liposomes,21 and gold nanorings,22, 23 have NIR absorption spectra that overlap with the OCT light source spectra, thus improving contrast by increasing the spectral signature of abnormal tissues. In highly scattering human tissues, such absorbing contrast agents should provide stronger contrast effect than scattering contrast agents.…”

“…However, this absorption diminishes to almost zero beyond 900 nm and its extinction cross‐section ( σ t,OCT ) is relatively weak. Gold nanorods16–18 and nanocages19, 20 are a class of OCT‐absorbing contrast agents that exhibit strong NIR absorption between 800 and 900 nm due to the surface plasmon resonance effect. However, a longer wavelength OCT light source centered at around 1300 nm is preferred for tumor imaging due to the reduced background scattering at this wavelength.…”