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Spectrophotometric determination of hydralazine hydrochloride tablets using ninhydrin
Journal - Association of Official Analytical Chemists
|November 1, 1983
Summary
A new spectrophotometric assay accurately quantifies hydralazine HCl in tablets using a specific reaction with ninhydrin. This method is unaffected by other drugs and provides reliable results for pharmaceutical analysis.
Area of Science:
- Analytical Chemistry
- Pharmaceutical Analysis
Background:
- Hydralazine hydrochloride (HCl) is a widely used antihypertensive medication.
- Accurate quantification of hydralazine HCl in pharmaceutical formulations is crucial for quality control.
Purpose of the Study:
- To develop and validate a specific and reliable spectrophotometric method for the assay of hydralazine HCl in tablet dosage forms.
Main Methods:
- A colorimetric reaction between hydralazine and ninhydrin was employed.
- The colored product was measured spectrophotometrically at an absorption maximum of 442 nm.
- The reaction was optimized in a pH 3 buffer solution at room temperature.
Main Results:
- The developed method demonstrated high specificity for hydralazine, with no interference from common co-administered drugs.
- Spectroscopic studies (IR, MS) indicated the formation of a hydrazone product.
- Ultraviolet spectrophotometry revealed rapid degradation of hydralazine in dilute solutions containing alcohols.
Conclusions:
- The described spectrophotometric method offers a specific, sensitive, and reliable approach for hydralazine HCl determination in tablets.
- The findings highlight the importance of considering solvent effects on hydralazine stability during analysis and formulation.
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