Photoacoustic stability of gold nanorods embedded in biopolymeric scaffolds

摘要

Gold nanorods exhibit intense optical absorbance in the near-infrared window of principal interest for applications in biomedical optics making them appealing as contrast agents in photoacoustic imaging and selective photothermolysis of cancer. However their photoinstability under laser irradiation remains a drawback of practical concern. In particular, when GNRs are irradiated with nanosecond laser pulses in resonance with their plasmon oscillations, there may occur phenomena like reshaping into spherical particles, as well as fragmentation at higher optical fluences, which result into modifications of their optical absorption bands and substantial loss of photoacoustic conversion efficiency. In this contribution we present an investigation of the photostability of gold nanorods embedded in biomimetic scaffolds by means of photoacustic experiments.