Abstract
Objective: Assays based on redox reactions that involve proton transfer are vulnerable to artifactual findings in metabolic acidosis/alkalosis.
We evaluated the impact of pH on the measurement of blood glucose
by the glucose dehydrogenase/pyrroloquinoline quinone system used
in point-of-care-testing.
Methods: We applied a series of thermodynamic equations to adjust the Gibbs energy for the pyrroloquinoline quinone couple. This adjusts values taken under standard conditions to those more closely resembling the physiological state.
Results: Under standard conditions, the pyrroloquinoline quinone couple has Eo = −0.125 V whereas adjustment to the physiological state (pH 7.40, ionic strength 0.15 mol/L, and temperature 310.15°K) yields Eo ′ = −0.166 V. This corresponds to an uncertainty in blood glucose determination of approximately 0.13 mmol/L.
Conclusion: We have demonstrated that the impact of pH on blood glucose determination by the glucose dehydrogenase/pyrroloquinoline quinone system (under physiologically relevant conditions of ionic strength and temperature) is not clinically significant.
Methods: We applied a series of thermodynamic equations to adjust the Gibbs energy for the pyrroloquinoline quinone couple. This adjusts values taken under standard conditions to those more closely resembling the physiological state.
Results: Under standard conditions, the pyrroloquinoline quinone couple has Eo = −0.125 V whereas adjustment to the physiological state (pH 7.40, ionic strength 0.15 mol/L, and temperature 310.15°K) yields Eo ′ = −0.166 V. This corresponds to an uncertainty in blood glucose determination of approximately 0.13 mmol/L.
Conclusion: We have demonstrated that the impact of pH on blood glucose determination by the glucose dehydrogenase/pyrroloquinoline quinone system (under physiologically relevant conditions of ionic strength and temperature) is not clinically significant.
| Original language | English |
|---|---|
| Pages (from-to) | 72-74 |
| Number of pages | 3 |
| Journal | Laboratory Medicine |
| Volume | 54 |
| Issue number | 1 |
| Early online date | 17 Aug 2022 |
| DOIs | |
| Publication status | Published (in print/issue) - 5 Jan 2023 |
Bibliographical note
Publisher Copyright:© The Author(s) 2022. Published by Oxford University Press on behalf of American Society for Clinical Pathology. All rights reserved. For permissions, please e-mail: [email protected].
Keywords
- PQQ-dependent glucose dehydrogenase
- basic science
- capillary blood glucose
- chemistry
- clinical chemistry
- diabetes mellitus
