A high sensitivity chemiluminescence-based CMOS image biosensor for the detection of human interleukin 5 (IL-5)

In this study, a CMOS image sensor that converts light intensity to digital image data was used to detect human interleukin 5 (IL-5). Although the application of CMOS image sensors to biosensors is well known, a more sensitive method is needed to detect molecules with very low concentrations such as cytokines. For this reason, we have used a chemiluminescence reaction to increase the sensitivity of sandwich immunoassay in CMOS image sensor. Another approach used to obtain a high sensitivity response was the pixel counting analysis. By using pixel counting analysis, much more detailed luminescence signals can be obtained. The detection sensitivity of IL-5 we obtained in our experimental measurements was evaluated up to 0.1 pg/mL.