Pacific Rim Symposium on Surfaces, Coatings and Interfaces (PacSurf 2016)
    Biomaterial Surfaces & Interfaces Tuesday Sessions
       Session BI-TuP

Paper BI-TuP10
Photoacoustic Microscopic Imaging with Bone Targeted Near Infrared Fluorophore

Tuesday, December 13, 2016, 4:00 pm, Room Mauka

Session: Biomaterial Surfaces & Interfaces Poster Session
Presenter: TaeJoong Eom, Gwangju Institute of Science and Technology (GIST), Republic of Korea
Authors: T.J. Eom, Gwangju Institute of Science and Technology (GIST), Republic of Korea
H.D. Lee, Gwangju Institute of Science and Technology (GIST), Republic of Korea
Correspondent: Click to Email
In order to obtain 3D bone structure images, we should regard x-ray dose for CT imaging or ultrasound image confusing from other organs. By using a bone-specific near infrared (NIR) fluorophore functionalized by phosphonate groups, we demonstrate photoacoustic microscopy (PAM) system for in-vivo bone imaging with out regarding x-ray dose. The NIR light has certain key advantages for biomedical imaging, including relatively ultra low tissue absorption with red blood cell, reduced scatter, and minimal autofluorescence. Especially, the phosphonated NIR fluorophore targets bone tissue with high specificity and this property is inherent to the chemical structure of the fluorophore. Since the heptamethine indocyanine structure has absorption/emission spectrum at ~780/ ~800 nm and the quantum yield of fluorophore is around 10-20 %, the NIR fluorophore can be applied for PA imaging system. The most of surplus optical energy is transferred to the thermal energy which can generate acoustic signal. For the NIR pulse excitation, we applied a high power pulsed laser, which has output power of 600 mW, pulse duration of 1 ns, and repetition rate of 10 kHz at the center wavelength of 780 nm. The NIR fluorophores were administered intravenously into nude mouse to obtain in-vivo PA bone imaging. The foot and tail bone structures of mouse image were successfully obtained by scanning a PAM system with a single ultrasound transducer.