Mediaspace scheduled maintenance: Aug 25, 2026 07:00 - 12:00 AM. During this time, videos will be temporarily unavailable. Check status updates.

Lecture

Potentiometric Sensors

In course

MICRO-330: Sensors

Principes physiques et électronique utilisés dans les capteurs. Applications des capteurs. ...

Description

This lecture covers the principles of potentiometric sensors, focusing on the redox couple, electron exchange, equilibrium potential, and Nernst law. It also discusses the working mechanism of glass electrodes, ion-selective membranes, and ISFET sensors for measuring pH and ion concentrations.

This video is available exclusively on Mediaspace for a restricted audience. Please log in to MediaSpace to access it if you have the necessary permissions.

Watch on Mediaspace

Instructors (3)

Philippe Renaud

Philippe Renaud is Professor at the Microsystem Laboratory (LMIS4) at EPFL. He is also the scientific director of the EPFL Center of MicroNanoTechnology (CMI). His main research area is related to micronano technologies in biomedical applications (BioMEMS) with emphasis on cell-chips, nanofluidics and bioelectronics. Ph. Renaud is invloved in many scientifics papers in his research area. He received his diploma in physics from the University of Neuchâtel (1983) and his Ph.D. degree from the University of Lausanne (1988). He was postdoctoral fellow at University of California, Berkeley (1988-89) and then at the IBM Zürich Research Laboratory in Switzerland (1990-91). In 1992, he joined the Sensors and Actuators group of the Swiss Center for Electronics and Microtechnology (CSEM) at Neuchâtel, Switzerland. He was appointed assistant professor at EPFL in 1994 and full professor in 1997. In summer 1996, he was visiting professor at the Tohoku University, Japan. Ph. Renaud is active in several scientific committee (scientific journals, international conferences, scientific advisory boards of companies, PhD thesis committee). He is also co-founder of the Nanotech-Montreux conference. Ph. Renaud is committed to valorization of basic research through his involvement in several high-tech start-up companies.

Giovanni Boero

Herbert Shea

Official source

Related concepts (31)

Ion-selective electrode

An ion-selective electrode (ISE), also known as a specific ion electrode (SIE), is a transducer (or sensor) that converts the change in the concentration of a specific ion dissolved in a solution into an electrical potential. The voltage is theoretically dependent on the logarithm of the ionic activity, according to the Nernst equation. Ion-selective electrodes are used in analytical chemistry and biochemical/biophysical research, where measurements of ionic concentration in an aqueous solution are required.

Reference electrode

A reference electrode is an electrode that has a stable and well-known electrode potential. The overall chemical reaction taking place in a cell is made up of two independent half-reactions, which describe chemical changes at the two electrodes. To focus on the reaction at the working electrode, the reference electrode is standardized with constant (buffered or saturated) concentrations of each participant of the redox reaction. There are many ways reference electrodes are used.

PH meter

A pH meter is a scientific instrument that measures the hydrogen-ion activity in water-based solutions, indicating its acidity or alkalinity expressed as pH. The pH meter measures the difference in electrical potential between a pH electrode and a reference electrode, and so the pH meter is sometimes referred to as a "potentiometric pH meter". The difference in electrical potential relates to the acidity or pH of the solution. Testing of pH via pH meters (pH-metry) is used in many applications ranging from laboratory experimentation to quality control.

Reversal potential

In a biological membrane, the reversal potential is the membrane potential at which the direction of ionic current reverses. At the reversal potential, there is no net flow of ions from one side of the membrane to the other. For channels that are permeable to only a single type of ions, the reversal potential is identical to the equilibrium potential of the ion. The equilibrium potential for an ion is the membrane potential at which there is no net movement of the ion.

In chemistry, pH (piːˈeɪtʃ ), also referred to as acidity, historically denotes "potential of hydrogen" (or "power of hydrogen"). It is a scale used to specify the acidity or basicity of an aqueous solution. Acidic solutions (solutions with higher concentrations of hydrogen () ions) are measured to have lower pH values than basic or alkaline solutions. The pH scale is logarithmic and inversely indicates the activity of hydrogen ions in the solution. where [H+] is the equilibrium molar concentration (mol/L) of H+ in the solution.

Related lectures (33)

Electrochemistry Fundamentals

Covers the fundamentals of electrochemistry, focusing on cell potential, current production, and the relationship between current and reactant conversion.

Membrane potential: Cellular mechanisms MOOC: Cellular Mechanisms of Brain Function

Explains membrane potential, equilibrium potentials, and ion conductances' role in determining the membrane potential.

Electrochemical Cell: pH Calculation

Covers the calculation of pH in an electrochemical cell scenario involving copper and hydrogen electrodes.

Electrochemistry: Redox Reactions

Explores electrochemistry principles, redox reactions, standard potential, and electrolysis applications.

Galvanic Cells: Standard Potentials and Concentration Effects

Explores galvanic cells, standard potentials, concentration effects, equilibrium constants, and pH meters in concentration cells.

Related concepts (31)

Ion-selective electrode

Reference electrode

PH meter

Reversal potential