Development of a CMOS Imaging Device for Functional Imaging Inside the Mouse Brain

We propose the use of a CMOS image sensor for in vivo functional imaging of the mouse brain. A dedicated image sensor with 176 times 144 pixels array is designed, fabricated, and packaged to enable on-chip fluorescence imaging. Using this configuration, we have successfully performed imaging inside the intact mouse brain. Furthermore, we have demonstrated functional imaging inside the mouse brain. This is done in conjunction with a fluorogenic substrate, which detects the presence of serine protease inside the brain. By imaging the fluorescence signal upon injection of a stimulant, we have successfully measured the brain protease activity and accurately determined its reaction onset, which is close to 1 hr 28 min after injection of the stimulant. This method represents a new approach for neural imaging using an inexpensive CMOS imaging device