Measurement of ascorbate and dehydroascorbate contents in biological fluids

Area of Science:

• Biochemistry
• Analytical Chemistry

Background:

• Ascorbate (vitamin C) and its oxidized form, dehydroascorbate, are unstable in biological samples.
• Rapid degradation occurs during sample processing, affecting accurate quantification.
• Dehydroascorbate has a short half-life, particularly in plasma (approx. 2 minutes).

Purpose of the Study:

• To develop a reliable method for quantifying ascorbate and dehydroascorbate in biological fluids.
• To address the challenge of analyte instability during sample handling and analysis.

Main Methods:

• High-performance liquid chromatography (HPLC) was employed.
• The method was designed to require no pretreatment of biological fluid samples.
• Analysis was performed on samples such as human heparinized plasma and urine.

Main Results:

• The study highlights the significant instability of both ascorbate and dehydroascorbate.
• It was confirmed that dehydroascorbate levels are influenced by both ascorbate oxidation and dehydroascorbate degradation.
• The developed HPLC method allows for quantification without sample pretreatment, mitigating degradation issues.

Conclusions:

• Accurate quantification of ascorbate and dehydroascorbate necessitates addressing their inherent instability.
• The novel HPLC method provides a robust solution for measuring these analytes in biological fluids.
• This method simplifies sample processing and improves the reliability of vitamin C metabolite measurements.