Bao Hongchun, Boussioutas Alex, Jeremy Reynolds, Russell Sarah, Gu Min
Center for Micro-Photonics, Faculty of Engineering & Industrial Sciences, Swinburne University of Technology, Victoria, Australia.
Opt Express. 2010 Jan 18;18(2):1255-60. doi: 10.1364/OE.18.001255.
A compact endomicroscope is the only solution for transferring second harmonic generation (SHG) imaging into in vivo imaging and real time monitoring the content and structure of collagen. This is important for early diagnoses of different diseases associated with collagen change. A compact nonlinear endomicroscope using a double clad fiber (DCF) is newly employed in SHG imaging. The experiment shows the core of the DCF can maintain the linear polarization of the excitation laser beam in particular directions, and the degree of polarization of the excitation laser beam directly affects signal to noise ratio of SHG imaging. The nonlinear endomicroscope can display clear three dimensional (3D) SHG images of mouse tail tendon without the aid of contrast agents, which reveals the collagen fiber structure at different depths. The high resolution of SHG imaging from the endomicroscope shows that SHG imaging can reveal additional information about the orientation and degree of organisation of proteins and collagen fibers than two-photon-excited fluorescence imaging. Therefore SHG imaging offers endomicroscopy with additional channel of imaging for understanding more about biological phenomena.
紧凑型内窥显微镜是将二次谐波产生（SHG）成像应用于体内成像并实时监测胶原蛋白含量和结构的唯一解决方案。这对于与胶原蛋白变化相关的不同疾病的早期诊断非常重要。一种使用双包层光纤（DCF）的紧凑型非线性内窥显微镜最近被应用于SHG成像。实验表明，DCF的纤芯可以在特定方向上保持激发激光束的线性偏振，并且激发激光束的偏振度直接影响SHG成像的信噪比。该非线性内窥显微镜无需使用造影剂就能清晰显示小鼠尾腱的三维（3D）SHG图像，揭示了不同深度的胶原纤维结构。内窥显微镜的SHG成像高分辨率表明，与双光子激发荧光成像相比，SHG成像可以揭示更多关于蛋白质和胶原纤维的取向和组织程度的信息。因此，SHG成像为内窥显微镜提供了额外的成像通道，有助于更深入地了解生物现象。
