Amperometry

Amperometry in chemistry is the detection of ions in a solution based on electric current or changes in electric current.

Introduction of amperometry:-

This technique is based on the measurement of the current flowing through an electrochemical cell when a constant potential is applied to the electrodes.

Example: PO₂, electrode.

• The po₂ electrode is a complete electrochemical cell consisting of a small platinum cathode a Silver/ Silver chloride anode and potassium chloride in phosphate buffer.
• Then platinum cathode is covered by a thin film of electrolyte.
• It is separated from the test solution by a polypropylene membrane, which is permeable to gas.
• When no oxygen is present in the test solution the cathode is polarized and the current is almost zero.
• When the PO₂, electrode is dipped in a test solution, in the presence of oxygen in the sample a current develops due to the diffusion of oxygen from the test solution through the membrane to the cathodes where it gets reduced.
• The current is directly proportional to PO₂, in the test solution (Blood)