Tag Archives: potentiometry
Disposable ISE
Schematic diagram of a disposable ion-selective electrode created by screen-printing. In (a) a thin film of conducting silver is printed on a polyester substrate and a film of Ag2S overlaid near the bottom. In (b) an insulation layer with a … Continue reading
Enzyme Electrode
A gas-sensing electrode can be modified to create a potentiometric electrode that respond to a biochemically important species, such as enzymes. One example of an enzyme electrode is the urea electrode, which is based on the catalytic hydrolysis of urea by … Continue reading
Gas-Sensing Membrane Electrode
A number of membrane electrodes respond to the concentration of a dissolved gas. The basic design of a gas-sensing electrode consists of a thin membrane that separates the sample from an inner solution containing an ion-selective electrode. The membrane is … Continue reading
Liquid Membrane Ion-Selective Electrode
Another class of ion-selective electrodes uses a hydrophobic membrane containing a liquid organic complexing agent that reacts selectively with the analyte. Three types of organic complexing agents have been used: cation exchangers, anion exchangers, and neutral ionophores. One example of … Continue reading
Solid-State Ion-Selective Electrode
Schematic diagram of a solid-state electrode, the membrane for which is either a polycrystalline inorganic salt or a single crystal of an inorganic salt. We can fashion a polycrystalline solid-state ion-selective electrode by sealing a 1–2 mm thick pellet of … Continue reading
pH Electrode
Schematic diagram showing a combination glass electrode for measuring pH. The indicator electrode consists of a pH-sensitive glass membrane and an internal Ag/AgCl reference electrode in a solution of 0.1 M HCl. The sample’s reference electrode is a Ag/AgCl electrode … Continue reading
Schematic Diagram of a Potentiometric Electrochemical Cell
Shown here is the schematic diagram of a typical potentiometric electrochemical cell. The electrochemical cell consists of two half-cells, each consisting of an electrode immersed in a solution of ions whose activities determine the electrode’s potential. A salt bridge containing … Continue reading
Family Tree for Interfacial Electrochemical Techniques
Shown here is a family tree that highlights a number of interfacial electrochemical techniques. The specific techniques are shown in red, the experimental conditions are shown in blue, and the analytical signals are shown in green. At the first level, … Continue reading
Schematic Diagram of Manual Potentiometer
To measure the potential of an electrochemical cell under a condition of zero current we use a potentiometer. Shown here is a schematic diagram for a manual potentiometer, which consists of a power supply, an electrochemical cell with a working … Continue reading