title: Systematic Approach for Trace Level Quantification of 2-N-butyl-4-spirocyclopentane-2-imidazole-5-one Genotoxic Impurity in Irbesartan Using LC-MS/MS.
abstract: 2-N-butyl-4-spirocyclopentane-2-imidazoline-5-one has been highlighted as a potential genotoxic impurity in irbesartan. A sensitive LC-MS/MS method was developed and validated for the determination of 2-N-butyl-4-spirocyclopentane-2-imidazoline-5-one in irbesartan. Good separation between 2-N-butyl-4-spirocyclopentane-2-imidazoline-5-one and irbesartan was achieved with Symmetry C18 (100×4.6 mm, 3.5 μm) column using 65:35 v/v mixture of 0.1% formic acid and acetonitrile as mobile phase with a flow rate of 0.7 ml/min. The proposed method was specific, linear, accurate, and precise. The calibration curve shows good linearity over the concentration range of 0.1-2.0 μg/ml, which matches the range of limit of quantitation-20×limit of quantitation of estimated permitted level (1.0 μg/ml) of 2-N-butyl-4-spirocyclopentane-2-imidazoline-5-one. The method was validated as per International Conference on Harmonization guidelines and was able to quantitate 2-N-butyl-4-spirocyclopentane-2-imidazoline-5-one impurity at 1.0 μg/ml with respect to 2 mg/ml of irbesartan. 2-N-butyl-4-spirocyclopentane-2-imidazoline-5-one was not present in the three studied pure and formulation batches of irbesartan and the developed method was a good quality control tool for quantitation of 2-N-butyl-4-spirocyclopentane-2-imidazole-5-one at very low levels in irbesartan.
authors.affiliation: Department of Chemistry, Sri Venkateswara University, Tirupati-517 502, India.
authors.forename: A Vijaya Bhaskar
authors.initials: AV
authors.lastname: Reddy
authors.affiliation: Department of Chemistry, Sri Venkateswara University, Tirupati-517 502, India.
authors.forename: N
authors.initials: N
authors.lastname: Venugopal
authors.affiliation: Department of Chemistry, Sri Venkateswara University, Tirupati-517 502, India.
authors.forename: G
authors.initials: G
authors.lastname: Madhavi
authors.affiliation: Department of Chemistry, Sri Venkateswara University, Tirupati-517 502, India.
authors.forename: V
authors.initials: V
authors.lastname: Madhavi
authors.affiliation: Department of Chemistry, Sri Venkateswara University, Tirupati-517 502, India.
authors.forename: K Gangadhara
authors.initials: KG
authors.lastname: Reddy
keywords: ICH guidelines; Linearity; genotoxicity; irbesartan; method validation