Which electrode is used to measure pO2?

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Multiple Choice

Which electrode is used to measure pO2?

The key idea here is how oxygen is measured with an electrochemical sensor. A Clark oxygen electrode detects pO2 by allowing oxygen to diffuse through a membrane to a platinum cathode where it is reduced at a fixed potential. The resulting current is proportional to the amount of oxygen reacting, so the measured current directly reflects the partial pressure of oxygen in the sample. This amperometric approach is specifically designed for sensing dissolved oxygen, making it the standard choice for pO2. Other options don’t measure oxygen in this way. A glass membrane electrode is the classic pH sensor, responding to hydrogen-ion activity. A vancomycin-based liquid polymer would be a specialized selective membrane for binding specific molecules, not a general pO2 sensor. A solid-state crystal membrane is typical for solid-ion sensors or other analytes, not the oxygen amperometric measurement. The so-called Clark conductance electrode is really the Clark oxygen electrode in its usual form, which is the oxygen sensor described here.

The key idea here is how oxygen is measured with an electrochemical sensor. A Clark oxygen electrode detects pO2 by allowing oxygen to diffuse through a membrane to a platinum cathode where it is reduced at a fixed potential. The resulting current is proportional to the amount of oxygen reacting, so the measured current directly reflects the partial pressure of oxygen in the sample. This amperometric approach is specifically designed for sensing dissolved oxygen, making it the standard choice for pO2.

Other options don’t measure oxygen in this way. A glass membrane electrode is the classic pH sensor, responding to hydrogen-ion activity. A vancomycin-based liquid polymer would be a specialized selective membrane for binding specific molecules, not a general pO2 sensor. A solid-state crystal membrane is typical for solid-ion sensors or other analytes, not the oxygen amperometric measurement. The so-called Clark conductance electrode is really the Clark oxygen electrode in its usual form, which is the oxygen sensor described here.

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