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Updated: Jun 24, 2026

A Rapid and Specific Microplate Assay for the Determination of Intra- and Extracellular Ascorbate in Cultured Cells
Published on: April 11, 2014
Study and application of the interaction between asymmetrical porphyrin and ascorbic acid
1School of Chemistry & Chemical Engineering, University of Jinan, Jinan 250022, People's Republic of China.
A new method uses a special porphyrin and fluorescence to measure ascorbic acid. This technique, enhanced by micro-emulsions, accurately detects ascorbic acid in supplements.
Area of Science:
- Analytical Chemistry
- Biochemistry
- Materials Science
Background:
- Ascorbic acid (Vitamin C) is a vital biomolecule with diverse physiological roles.
- Accurate quantification of ascorbic acid is crucial for nutritional and clinical applications.
- Novel porphyrin derivatives offer potential as sensitive analytical probes.
Purpose of the Study:
- To investigate the interaction between 5,10,15-triphenyl-20-pyridyl porphyrin and ascorbic acid.
- To develop a novel fluorescence quenching method for ascorbic acid determination.
- To validate the method for analyzing ascorbic acid in commercial tablet formulations.
Main Methods:
- Fluorophotometry was employed to study the porphyrin-ascorbic acid interaction.
- The influence of Cetyltrimethylammonium Bromide (CTMAB) micro-emulsion on spectral properties was examined.
- A fluorescence quenching assay was established based on the observed linear relationship.
Main Results:
- The absorption and fluorescence intensity of the porphyrin were significantly enhanced by CTMAB micro-emulsion.
- Ascorbic acid induced a decrease in porphyrin fluorescence intensity (quenching).
- A linear correlation was observed between fluorescence quenching and ascorbic acid concentration within a specific range.
Conclusions:
- A sensitive and reliable fluorescence quenching method for ascorbic acid determination was successfully developed.
- The method demonstrated satisfactory performance in the analysis of ascorbic acid in commercial tablets.
- The quenching mechanism was identified as static quenching, involving interactions between the porphyrin and ascorbic acid.
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