Optoacoustic response of gold nanorods in soft phantoms using high-power diode laser assemblies at 870 and 905 nm

In the present paper we show the optoacoustic (OA) response of two solutions of gold nanorods dispersed in distilled water (0.8 mg/ml) and hosted in tissue-like phantoms by using small arrays of HPDLs at 870 and 905 nm as excitation sources. The HPDLs are coupled to a 7-to-1 optical fiber bundle with output diameter of 675 mu m. Each solution of gold nanorods exhibits an absorption peak close to the operating wavelength, i.e. similar to 860 nm and similar to 900 nm, respectively, to optimize the generation of OA signals. The phantoms are made of agar, intralipid and hemoglobin to simulate a soft biological tissue with reduced properties of scattering. Three 3-mm diameter tubes done in the phantoms at different depths (0.9 cm, 1.8 cm, and 2.7 cm) have been filled with gold nanorods. In this way, OA signals with appreciable SNR are generated at different depths in the phantoms. The high OA response exhibited by gold nanorods suggests their application in OA spectroscopy as exogenous contrast agents to detect and monitor emerging diseases like metastasis and arteriosclerotic plaques.

sentinel lymph-nodes; in-vivo; photoacoustic microscopy; photothermal therapy; high-resolution; tomography; limitations; breast

Optoacoustic response of gold nanorods in soft phantoms using high-power diode laser assemblies at 870 and 905 nm Articles