Flow injection amperometric detection of ascorbic acid using a Prussian Blue film-modified electrode

Area of Science:

• Electrochemistry
• Analytical Chemistry

Background:

• Ascorbic acid (Vitamin C) is a vital biomolecule with numerous health benefits.
• Accurate quantification of ascorbic acid is crucial in pharmaceutical analysis and quality control.

Purpose of the Study:

• To develop and validate a PB film-modified electrode for the amperometric detection of ascorbic acid.
• To assess the sensitivity, stability, and reproducibility of the modified electrode for flow injection analysis.
• To determine the accuracy of the method by analyzing ascorbic acid in pharmaceutical products.

Main Methods:

• Fabrication of a PB film-modified electrode.
• Utilizing the modified electrode as an amperometric detector in a flow injection analysis (FIA) system.
• Establishing a calibration curve for ascorbic acid over a specified concentration range.
• Evaluating method performance through sensitivity, stability, reproducibility, and detection limit assessments.
• Comparing results with a standard triiodide-based method for pharmaceutical samples.

Main Results:

• The PB film-modified electrode demonstrated good sensitivity, stability, and reproducibility.
• A linear calibration curve for ascorbic acid was obtained from 5.0x10(-6) to 1.0x10(-3) mol L(-1) (R=0.999).
• The method achieved a low detection limit of 2.49x10(-6) mol L(-1).
• The relative standard deviation for replicate injections was 2.5%, indicating high precision.
• Assay results for pharmaceutical products showed good agreement with a conventional method.

Conclusions:

• The PB film-modified electrode is a suitable and reliable amperometric detector for the quantitative determination of ascorbic acid.
• The developed flow injection analysis method offers high sensitivity, accuracy, and precision for analyzing ascorbic acid in pharmaceutical formulations.
• This approach provides a valuable alternative for routine quality control of ascorbic acid in pharmaceutical products.