A specific high-performance liquid chromatography assay for dehydroascorbic acid shows an increased content in CLL...

Area of Science:

• Biochemistry
• Analytical Chemistry
• Hematology

Background:

• Dehydroascorbic acid (DHA) is the oxidized form of vitamin C.
• Accurate quantification of DHA is crucial for understanding its role in various physiological and pathological processes.
• Existing methods for DHA assay lack sufficient sensitivity and specificity.

Purpose of the Study:

• To develop and validate a sensitive and specific method for quantifying dehydroascorbic acid.
• To measure DHA levels in lymphocytes from healthy individuals and patients with chronic lymphocytic leukemia (CLL).

Main Methods:

• Development of a high-performance liquid chromatography (HPLC) method with UV detection for DHA assay.
• Separation of DHA from ascorbic acid, followed by reduction with dithiothreitol.
• Quantification of DHA as ascorbic acid after rechromatography.

Main Results:

• The developed HPLC method offers a 40-fold increase in sensitivity compared to existing procedures, detecting as little as 22 pmol of DHA.
• Significantly higher concentrations of DHA were observed in leukemic lymphocytes (21.80 +/- 3.55 nmol/10(8) cells) compared to normal lymphocytes (9.32 +/- 1.15 nmol/10(8) cells).
• Elevated DHA levels in CLL were not attributable to the increased proportion of B lymphocytes.

Conclusions:

• The novel HPLC method provides a highly sensitive and reliable means for DHA quantification.
• Leukemic lymphocytes in CLL exhibit elevated dehydroascorbic acid levels.
• This technique is valuable for analyzing DHA in biological samples with limited material or low analyte concentrations.