[19a-E202-1~12] 12.7 Biomedical Engineering and Biochips

▼ [19a-E202-6] CMOS Image Sensor for FRET Imaging Using Hybrid Emission Filter

〇(M1)Natcha Kulmala¹, Wan Shen Hee¹, Kiyotaka Sasagawa¹, Makito Haruta¹, Jun Ohta¹ (1.Nara Institute of Science Technolgy)

Keywords:CMOS image sensor, hybrid filter, FRET

Förster resonance energy transfer (FRET) has been widely used in order to observe an interaction between molecules. In this work, we propose and demonstrate a small and compact lensless device by using a CMOS image sensor for FRET imaging. Due to a tiny size and good field-of-view, it is suitable for long term cell observation and in-vivo imaging. To detect FRET signals, we developed the high performance filters to detect cyan and yellow fluorescence, simultaneously. In this work, the hybrid filter structure composed of two layers. The top layer is excitation light removal layer, it consists of long pass interference filter, fiber optic plate (FOP), short pass interference filter and pale-yellow absorption longpass filter. Then, the lowest layer, alternately lines of yellow-green and blue filter coated on the photodiode to form selective detection layer in order to detect the target fluorescence light. In the experiment, we observed two types of fluorescent microbeads to demonstrate two-color fluorescent imaging using our device. This device is able to simultaneously detecting cyan and yellow fluorescent light, respectively. The results show that our lens-free device can detect and capture fluorescence in the cyan and yellow color regions separately. Afterward, this device will be applied to in-vitro FRET imaging to observe the FRET activity in the cultured cell.