Deep ultraviolet light based wide-field fluorescence microscope for brain imaging

ABSTRACT Three-dimensional (3D) cellular scale imaging techniques that improve our understanding of the brain architecture is crucial for structural and functional integration and analysis of normal and pathological conditions in the brain. We have developed a wide-field fluorescent microscope using deep ultra violet (DUV) light emitting diode as the illumination source. This microscope employs oblique illumination of deep UV light and the optical sectioning is obtained on the tissue surface over a few micron thickness; largely attributed to the large absorption and hence low tissue penetration of the DUV light. Fluorescence emissions in the visible range that are spectrally separates allows for multiple channel of fluorophore detection using single or a combination of dyes. The fluorescence signal is captured using water immersion objectives and a color camera. Arduino Mega 2560 controlled 3-axis motorised microscope stage is developed for obtaining the wide-field imaging. To enable 3D imaging, the microscope setup is integrated with vibrating microtome that can slice thin sections for serial block-face imaging. In this paper, we show the versatility of the DUV microscope as a microscopy tool for use in neuroscience labs for a range of 2D brain imaging applications. We also present its applicability for 3D imaging of rodent brain in combination with whole brain staining protocol.