All authors read and approved the final manuscript.”
“Background Graphene has two sp 2-bonded carbon atoms, which make its structure apparently look like a honeycomb crystal as seen in Figure 1[1–3].

Because of its unique properties, graphene has attracted huge interest mainly in the electrical, physical, chemical, and even biological fields [4, 5]. Figure 1 Monolayer graphene atom arrangement with only one atom thickness. Nowadays, ion-sensitive field-effect transistors (ISFETs) have caught much attention due to their advantages such as small size and the possibilities for mass production [6, 7]. Their short and consistent response times are very favorable to the electronics industry [8, 9]. ISFETs introduce Lenvatinib datasheet new features such as the integration of data processing and compensation circuits in the similar circuit for this type of sensors [10–12]. By altering the gate material, depositing layers of selective membrane or a bio-recognition element onto the gate, variance of selectivity can be achieved [13, 14]. After the process of depositing, the sensors are now called chemically sensitive FETs [15, 16]. Initially, heterogeneous membranes

of silver halides and membranes based on polyvinyl chloride (PVC) have been used for ISFET [17, 18]. Due to poor adherence between PVC base membrane and ISFET surface and inconsistent results, scientists explore for a new type of membrane [18, 19]. That is where photocured polymers, which caspase inhibitor are compatible with the proposed photolithography techniques, come in [19, 20]. They have the properties of a higher adherence string of the salinized ISFET gate’s surface [21].

In order to expand ion-selective membranes, numerous polymers such as polysiloxanes, polyurethanes, and different methacrylate-derived polymers have been reported to be good candidates [22, 23]. These new polymers show promising results regarding consistency and longer stability compared to PVC membranes [24]. In addition, almost all effective ion-based Adenosine triphosphate ISFETs were developed for clinical analyses and CP-690550 environmental applications [24]. Recently, microelectronic advances have been exploited and applied to improve ISFET fabrication methods [25, 26]. Because of the electrolyte’s ionic properties, electrical parts of ISFETs cannot have contact with liquid and only the gate area is open [27]. Due to its organic nature, the gate material for ISFETs is intrinsically sensitive to pH changes [28, 29]. On the other hand, all enzymes are sensitive to pH changes, but extremely high or low pH values can make these enzymes lose their sensitivity [30, 31]. pH is also a main factor in enzyme stabilities [32]. Each enzyme includes a suitable or optimal pH stability range [30, 32]. Apart from temperature and pH, ionic strength can also affect the enzymatic reaction [33].