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Updated: May 9, 2026
11:56
A Rapid and Specific Microplate Assay for the Determination of Intra- and Extracellular Ascorbate in Cultured Cells
Published on: April 11, 2014
A convenient method for measuring blood ascorbate concentrations in patients receiving high-dose intravenous
Yan Ma1, Garrett G Sullivan, Elizabeth Schrick
1Department of Pharmacology, Toxicology and Therapeutics, University of Kansas Medical Center, Kansas City, KS 66160, USA.
Journal of the American College of Nutrition
|July 27, 2013
Summary
Fingerstick blood glucose monitors can estimate high blood ascorbate levels after intravenous infusions. However, this method is inaccurate for baseline levels and can falsely elevate glucose readings, contraindicating insulin use.
Area of Science:
- Biochemistry
- Clinical Chemistry
- Medical Diagnostics
Background:
- High-dose intravenous ascorbate is used therapeutically.
- Accurate monitoring of blood ascorbate levels is crucial.
- Current methods like HPLC are complex and time-consuming.
Purpose of the Study:
- To evaluate fingerstick blood glucose (FSBG) monitors as a simple method for estimating blood ascorbate.
- To compare FSBG-derived ascorbate values with high-performance liquid chromatography (HPLC) measurements.
Main Methods:
- 33 participants received IV ascorbate infusions.
- FSBG readings were taken pre- and post-infusion.
- The difference in FSBG readings was correlated with HPLC-measured ascorbate concentrations.
Main Results:
- A linear correlation was observed between FSBG-derived and HPLC-measured ascorbate values.
- Correlation was consistent across healthy, diabetic, and cancer patient groups.
- FSBG method provided approximate estimation of high blood ascorbate (>50 mg/dL) without correction.
Conclusions:
- FSBG monitors offer a simple, approximate method for estimating high post-infusion blood ascorbate.
- The method is not accurate for baseline or low ascorbate concentrations.
- FSBG readings are erroneously elevated post-infusion, necessitating caution regarding insulin administration.
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