Indirect determination of captopril by AAS

Area of Science:

• Analytical Chemistry
• Spectroscopy
• Pharmaceutical Analysis

Background:

• Captopril (KPL) is a widely used pharmaceutical agent.
• Accurate quantification of KPL in pharmaceutical preparations is crucial for quality control.
• Existing analytical methods may have limitations in sensitivity or specificity.

Purpose of the Study:

• To develop and validate a novel indirect method for captopril determination.
• To utilize atomic absorption spectrometry (AAS) for sensitive and accurate KPL quantification.
• To establish a reliable analytical procedure for pharmaceutical preparations containing captopril.

Main Methods:

• Indirect determination of captopril (KPL) via complexation with excess palladium (Pd(II)).
• Separation of unreacted Pd(II) using a cationic ion-exchange resin.
• Quantification of retained Pd(II)-KPL complex in the effluent by AAS.
• Characterization of the solid Pd(II)-KPL complex using elemental analysis, TG, conductance, IR, and 1H-NMR spectroscopy.

Main Results:

• A linear relationship was observed between absorbance and KPL concentration (correlation coefficient 0.9939).
• The method demonstrated adherence to Beer's law in the range of 1-40 microg/ml.
• The standard deviation was found to be 0.039 (n=5), indicating good precision.
• The Pd(II)-KPL complex was successfully synthesized and characterized.

Conclusions:

• The developed indirect AAS method provides a sensitive and accurate approach for captopril determination in pharmaceutical formulations.
• The ion-exchange separation step enhances the specificity and reliability of the assay.
• The method's validation through correlation coefficient and standard deviation supports its utility in pharmaceutical quality control.