Analysis of enzyme-immobilized polyion complex membrane on label free acetylcholine ion image sensor

32 × 32 acetylcholine (ACh) image sensor was successfully obtained for a real time ACh distribution image. In this work, the sensor using optimized enzyme-immobilized polyion complex membrane composed of poly-L-lysine and poly (sodium 4-styrensulfonate) was measured with better stability and repeatability. The optimized polyion complex membrane was fabricated with better adhesion to the sensor. As a result, the noise was reduced and the sensor can be measured repeatedly unless the enzyme is inactivated and the membrane is removed.