In that study, a new type of ISFET charge sensor was developed for the determination of maltose-induced
conformational change in maltose binding protein (MBP). As shown in Figure 4, when treated
with maltose on the MBP-modified ISFET surface, the structural transition of MBP took place,
leading to a substantial drop in the drain current of the ISFET device. The authors demonstrated
that the ISFET charge sensor can be effectively utilized to evaluate the intramolecular
conformational change in proteins.