A two-dimensional (2D) gold nanostructure is used to optically generate high frequency ultrasound. The structure consists of 2D arrangements of gold nanoparticles, sandwiched between a transparent substrate and a 4.5 μm thick polydimethylsiloxane (PDMS) layer. The acoustic signal displays significant improvements compared to a bulk black PDMS films (the current state of the art) at frequencies from 50 to 100 MHz. The high optical extinction ratio of the gold nanostructure provides a convenient method to construct an integrated transmit/receive optoacoustic array. These results show that a 2D gold nanostructure can be used to produce high frequency arrays for ultrasound imaging.
Bibliographical noteFunding Information:
This work is supported in part by NIH under Grant Nos. EB003455, EB003449, and EB004933. The authors thank the Resource Center for Medical Ultrasonic Transducer Technology at the University of Southern California for supplying the high frequency transducers.