Patterning an enzyme-membrane of bio-image sensor using lithography technique

To detect several kinds of neurotransmitters in brain tissue simultaneously, we developed a pattering technique that harden ultraviolet (UV)-curing resin containing an enzyme to fabricate a enzyme-membrane by using lithography method. In this study, an apyrase-membrane was patterned on a 128×128 pixel ion-image sensor to monitor the distribution and dynamics of adenosine triphosphate (ATP) activity. The highest response was 0.035 V with 1 mM ATP solution. From the states of voltage distribution, we confirmed that the apyrase-membrane is reacting with normal distribution curves for ATP solution of various concentration. The limit of detection (LOD) of the sensor was 0.001 mM ATP concentration. Based on these measured characteristics, the apyrase-containing UV-curing resin was patterned by lithography technology. The size of a patterned membrane was 250×250 μm2. Sequential images are acquired during the reaction and interpreted. To make multi-ion-image sensor for simultaneous analysis of various neurotransmitters, the suggested technique will be applied to fabricate other enzyme-containing membranes.