Photoacoustic Imaging of Multiple Targets Using Gold Nanorods

• Published in: IEEE transactions on ultrasonics, ferroelectrics, and frequency control ferroelectrics, and frequency control, 2007-08, Vol.54 (8), p.1642-1647
• Main Authors: Li, P.-C., Wei, C.-W., Liao, C.-K., Chen, C.-D., Pao, K.-C., Wang, C.-R.C., Wu, Y.-N., Shieh, D.-B.
• Format: Article
• Language: English
• Subjects: Absorption; Animals; Aspect ratio; Biological and medical sciences; Biomedical imaging; Biomedical optical imaging; Blotting, Western; Cancer; Contrast Media; Gold; Gold - chemistry; Humans; Image Enhancement - methods; Imaging; Investigative techniques, diagnostic techniques (general aspects); Laser-Doppler Flowmetry - instrumentation; Laser-Doppler Flowmetry - methods; Lasers; Liver Neoplasms - diagnostic imaging; Medical sciences; Mice; Miscellaneous. Technology; Nanoparticles; Nanorods; Nanotubes - chemistry; Noise levels; Optical imaging; Optical surface waves; Pathogens; Surface treatment; Tumor Cells, Cultured - diagnostic imaging; Ultrasonic investigative techniques; Ultrasonography; Urinary Bladder Neoplasms - diagnostic imaging; Wavelengths
• ISSN: 0885-3010; 1525-8955
• DOI: 10.1109/TUFFC.2007.435

Photoacoustic (PA) imaging has been used mainly for anatomical and functional imaging. Although functionalized nanoparticles also have been developed for PA molecular imaging, only single targeting has been demonstrated. In this study, PA imaging of multiple targets using gold nanorods is demonstrated experimentally using HER2 and CXCR4 as target molecules. The two corresponding monoclonal antibodies were conjugated to two types of gold nanorod with different aspect ratios. Gold nanorods with mean aspect ratios of 5.9 and 3.7 exhibited peak optical absorptions at 1000 and 785 nm, respectively. Appropriate selection of laser irradiation wavelength enhances PA signals by 7-12 dB and allows signals from gold nanorods corresponding to specific bindings to be distinguished. This approach potentially allows the expression levels of different oncogenes of cancer cells to be revealed simultaneously.