Stability Indicating Derivative Spectrophotometric Method for Determination of Trandolapril in Bulk and in Formulation

Trandolapril is an oral angiotensin-converting enzyme (ACE) inhibitor approved by the USFDA for the therapy of hypertension and congestive heart failure. This paper describes the validation of zero- and first-order derivative UV spectrophotometric methods for the estimation of trandolapril in bulk and in its marketed tablet formulation. Preliminary spectrophotometric determination of the drug was carried out in phosphate buffer pH 2.0 or 0.1 N HCl. A total of 17 parametric method variants were investigated out of which three variants employing peak–zero (P–0) and peak–peak (P–P) techniques were validated with respect to linearity, accuracy, precision, and robustness. The developed methods were also assessed for stability indicating potential in force degraded solutions. Linearity was observed in the concentration range of 1.0–70.0 μg/mL with an excellent correlation coefficient (r²) ranging from 0.9981 to 0.9998. The limits of assay detection values were found for the range of 0.88–1.23 μg/mL, and quantitation limits ranged from 2.66 to 6.09 μg/mL for the proposed methods. The proposed methods were extended to the quantification of the drug in its marketed tablet formulation with good recoveries (90–98%).