Dihydralazine sulfate analysis using 2-methyl-o-nitropyridine-6-carboxaldehyde

Area of Science:

• Analytical Chemistry
• Pharmaceutical Analysis

Background:

• Dihydralazine sulfate requires accurate quantification for therapeutic efficacy and safety.
• Existing analytical methods may lack sensitivity, selectivity, or applicability to complex formulations.

Purpose of the Study:

• To develop a sensitive and selective colorimetric assay for dihydralazine sulfate.
• To validate the assay for quantitative analysis in pharmaceutical products and as a stability-indicating method.

Main Methods:

• A colorimetric reaction between dihydralazine sulfate and 2-methyl-3-nitropyridine-6-carboxaldehyde at pH 4.
• Spectrophotometric quantification of the resulting orange color at 450 nm.
• Analysis of dihydralazine sulfate in commercial tablet formulations, including stability studies.

Main Results:

• The assay demonstrated high sensitivity with a lower limit of detection of 1 µg/ml.
• The developed method showed no interference from common excipients or other drugs.
• The color produced was stable for at least 24 hours.
• Successful determination of dihydralazine sulfate in various commercial tablets was achieved.

Conclusions:

• A novel, sensitive, and selective colorimetric assay for dihydralazine sulfate has been successfully developed.
• The method is robust, interference-free, and applicable for quality control of pharmaceutical formulations.
• The assay is suitable for use as a stability-indicating method, ensuring drug integrity over time.