Butyryl cholinesterase of different origin along with variations of the time of enzyme immobilization on the potentiometric transducer surface is offered to control the ion sensitive field effect transistor (ISFET)-based biosensor sensitivity. Because butyryl cholinesterase has been already used to develop the sensors for heavy metals, organophosphorus/carbamate pesticides, and steroidal glycoa...

A time-of-flight-type flow-velocity sensor employing the in-situ electrochemically generation of ion-tracers is developed. The sensor consists of an ion generator and two downstream-placed pH-sensitive Ta2O5-gate ISFETs (ion-sensitive field-effect transistor) that detect generated Hor OH-ions. The results of the developed flow-velocity sensor under different modes of ion generation are presente...

Acid or base concentrations can be determined by coulometric titration. A new alliridium oxide sensor-actuator device is presented, of which the titrant is generated by a reversible redox reaction occurring in the electroactive iridium oxide actuator electrode, and the equivalence point in the titration curve is detected by the pH-sensitive iridium oxide sensor. The advantage with respect to th...

The ion-sensitive field effect transistors (ISFETs), proposed little over 50 years ago, today make the most promising devices for lab-on-a-chip, implantable, and point-of-care (POC) diagnostics. Their compatibility with CMOS (Complementary Metal Oxide Semiconductor) technology low cost through mass production have been driving factors so far. Nowadays, they are also being developed in flexible ...

The Ion-Sensitive Field-Effect Transistor (ISFET) is one of the most popular pH sensors traditionally using to measure hydrogen ion concentration (pH) electrolytic solutions. It developed from Metal Oxide Semiconductor (MOSFET) by replacing gate electrode with an solution be tested, and a reference metal immersed in that solution. Basic principle ISFET operation based on standard NMOS structure...

A monolithically integrated ISFET sensor array and interface circuit are described. A new high-density, low-power source-drain follower was developed for the sensor array. ISFETs were formed by depositing Au/Ti extended-gate electrodes on standard MOSFETs, then thin silicon nitride layers using catalytic chemical vapor deposition and/or SU-8 protective layers were formed on the extended-gate el...

This letter introduces an ISFET-based integrate and fire neuron forming the front-end of a chemical pixel sensor. With the sense data being encoded in the spike domain, i.e. asynchronous/continuous time and discrete value, it is directly compatible with asynchronous communication hardware, e.g. Address Event Representation. The circuit is shown to be tunable to yield a linear relation with both...