Quantitative estimation of irbesartan in two different matrices and its application to human and dog bioavailability studies using LC–MS/MS

The determination of two analogues of 4-(azidomethyl)-1,1'-biphenyl as potential genotoxic impurities in the active pharmaceutical ingredient of several sartans containing a tetrazole group

4'-(azidomethyl)-[1,1'-biphenyl]-2-carbonitrile (GTI-azide-1) and 5-(4'-(azidomethyl)-[1,1'-biphenyl]-2-yl)-1H-tetrazole (GTI-azide-2) are potentially genotoxic impurities that can be present at trace levels in the active pharmaceutical ingredients and drug products of sartans containing a tetrazole group. A method of high-performance liquid chromatography coupled with mass spectrometry, that allows the determination of those genotoxic impurities at sub-ppm level relative to the active pharmaceutical ingredient, was developed. The method utilises a very efficient liquid chromatograph Waters Acquity I-Class coupled with a highly sensitive tandem mass spectrometer Xevo TQ-XS. The separation was achieved on a column Acquity UPLC BEH Shield RP18 1.7 μm employing a linear elution gradient. The mass spectrometer was used with a heated electrospray ionization. The method was found to be sufficient in terms of sensitivity, linearity, precision, accuracy, selectivity and robustness and is easily applicable in the pharmaceutical quality control environment. The method allows for accurate quantification of both impurities GTI-azide-1 and GTI-azide-2 at levels below 1/10^th of the specification limit, which is crucial in the context of pharmaceutical analysis. The limit of quantification was determined to be 0.033 ppm and 0.025 ppm for GTI-azide-1 and GTI-azide-2, respectively.

Irbesartan (a comprehensive profile)

Irbesartan, (2-butyl-3-({4-[2-(2H-1,2,3,4-tetrazol-5-yl)phenyl]phenyl}methyl)-1,3-diazaspiro[4.4]non-1-en-4-one), is a member of non-peptide angiotensin II receptor antagonists used worldwide in the treatment of hypertension and diabetic nephropathy in hypertensive patients with type 2 diabetes, elevated serum creatinine, and proteinuria. Irbesartan can be used alone or in combination with other antihypertensive agents (e.g., hydrochlorothiazide). These combination products are indicated for hypertension in patients with uncontrolled hypertension with monotherapy or first line in patients not expected to be well controlled with monotherapy. Irbesartan is also indicated for the treatment of diabetic nephropathy in patients with type 2 diabetes and hypertension, an elevated serum creatinine, and proteinuria. Irbesartan exerts its action mainly via a selective blockade action on AT1 receptors and the consequent reduced pressor effect of angiotensin II. This article discusses, by a critical comprehensive review of the literature on irbesartan in terms of its description, names, formulae, elemental composition, appearance, and therapeutic uses. The article also discusses the methods for preparation of irbesartan, its physical-chemical properties, analytical methods for its determination, pharmacological-toxicological properties, and dosing information.

New ultra-performance liquid chromatography-tandem mass spectrometry method for the determination of irbesartan in human plasma

With the objective of reducing analysis time and maintaining good efficiency, there has been substantial focus on high-speed chromatographic separations and ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) is a preeminent analytical tool for rapid biomedical analysis. In this study a simple, rapid, sensitive, and specific ultra-performance liquid chromatography-MS/MS method was developed and validated for quantification of the angiotensin II receptor antagonist, irbesartan (IRB), in human plasma. After a simple protein precipitation using methanol and acetonitrile, IRB and internal standard (IS) telmisartan were separated on Acquity UPLC BEH C18 column (50 mm × 2.1 mm, i.d. 1.7 μm, Waters, Milford, MA, USA) using a mobile phase consisted of acetonitrile: methanol: 10 mM ammonium acetate (70: 15: 15 v/v/v) with a flow rate of 0.4 mL/min and detected MS/MS in negative ion mode. The ion transitions recorded in multiple reaction monitoring mode were m/z 427.2→193.08 for IRB and m/z 513.2→469.3 for IS. The assay exhibited a linear dynamic range of 2-500 ng/mL for IRB in human plasma with good correlation coefficient of (0.995) and with a lower limit of quantitation of 2 ng/mL. The intra- and interassay precisions were satisfactory; the relative standard deviations did not exceed 9.91%. The proposed UPLC-MS/MS method is simple, rapid, and highly sensitive, and hence it could be reliable for pharmacokinetic and toxicokinetic study in both animals and humans.