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Updated: Jun 28, 2026
10:22
Improved UPLC-UV Method for the Quantification of Vitamin C in Lettuce Varieties (Lactuca sativa L.) and Crop Wild Relatives (Lactuca spp.)
Published on: June 30, 2020
Food analyses: a new calorimetric method for ascorbic acid (vitamin C) determination.
M L Antonelli1, G D'Ascenzo, A Laganà
1Dipartimento di Chimica, Università degli Studi di Roma 'La Sapienza', P.le Aldo Moro 5, 1-00185 Rome, Italy.
Talanta
|October 31, 2008
Summary
A new microcalorimetric method accurately measures ascorbic acid (vitamin C) in foods and pharmaceuticals. This enzyme-catalyzed assay is fast, requires minimal sample preparation, and was validated against HPLC.
Area of Science:
- Analytical Chemistry
- Biochemistry
- Enzymology
Background:
- Ascorbic acid (vitamin C) is a vital nutrient with diverse biological roles.
- Accurate quantification of vitamin C is crucial for food quality and pharmaceutical efficacy.
- Existing analytical methods may require complex sample preparation or lack specificity.
Purpose of the Study:
- To develop and validate a novel microcalorimetric method for ascorbic acid determination.
- To assess the method's applicability to various food and pharmaceutical samples.
- To investigate the stability of vitamin C under different storage conditions.
Main Methods:
- A microcalorimetric approach utilizing ascorbate oxidase (A.O.) enzyme catalysis for specific vitamin C oxidation.
- Establishment of calibration curves under defined conditions (25°C, pH 5.6, [A.O.]=11 IU ml⁻¹).
- Application to diverse samples, with analysis time of approximately 20 minutes per sample.
Main Results:
- The method demonstrated linearity in the range of 3–270 mg L⁻¹ ascorbic acid.
- Successfully quantified vitamin C in multiple food and pharmaceutical matrices.
- Validated against a High-Performance Liquid Chromatography (HPLC) assay, confirming reliability.
Conclusions:
- The developed microcalorimetric method offers a sensitive, specific, and efficient means for vitamin C analysis.
- The assay is suitable for routine analysis without extensive sample pre-treatment.
- The method provides a reliable alternative for quality control in food and pharmaceutical industries.
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