광음향 진단법- 고출력 레이저 다이오드 현미경 기반 고급 시스템

Abstract

Photoacoustic microscopy (PAM) is an efficient, noninvasive and three-dimensional imaging modality capable of imaging organs, tissues, and cellular structures with high resolution. However, the popularity of the PAM systems generally used are inconvenient and expensive solid-state laser source. Therefore, a cost-efficient and compact PAM system using the high power pulsed laser diode (PLD) has been used to develop its advantages in biological applications. In this study, two significantly improvement configuration PAM of using PLD is presented. A low loss microscopy objective lens is used to persist the laser power which set up two PAM systems: transmission mode (TM) and reflection mode (RM) PAM. The commercially focused transducer with the central frequency of 5 MHz is employed to pick up the photoacoustic (PA) signal which was rebuilt to 2D images via MATLAB software. The lateral resolution of two PAM systems can be estimated to ~ 40 µm by imaging carbon fiber. On the other hand, we imaged the phantom, ex vivo, in vivo with poly-pyrrole methylene blue nanoparticles (PPy-MB NPs) as a contrast agent to evaluate the productivity of our PAM systems. Moreover, we also perform in vivo mouse ear experiment to further demonstrated the feasibly of using high power PLD for PAM systems. The results of these experiments suggest that our PLD PAM system is potential for developing of photoacoustic imaging tool.