Question

When using optical methods of measuring PO2, such as phosphorescence or fluorescence quenching, the __the PO2 is in the sensor, the __the phosphorescence or fluorescence.

A) Higher, lower
B) Lower, higher
C) Same, lower
D) Same, higher

Answer 1

In the context of optical methods of measuring PO2, a higher partial pressure of oxygen (PO2) in the sensor leads to lower levels of emitted phosphorescence or fluorescence due to increased quenching.

Step-by-step explanation:

When using optical methods of measuring PO2, such as phosphorescence or fluorescence quenching, the higher the PO2 is in the sensor, the lower the phosphorescence or fluorescence. This relationship is evident because the presence of oxygen affects the longevity of the excited state of the fluorescent molecules; higher levels of oxygen lead to increased quenching, which results in a decrease in the intensity of the fluorescence or phosphorescence emitted.