Limits...
Development of a novel 96-microwell assay with high throughput for determination of olmesartan medoxomil in its tablets.

Darwish IA, Wani TA, Khalil NY, Al-Shaikh AA, Al-Morshadi N - Chem Cent J (2012)

Bottom Line: The limits of detection and quantitation were 0.3 and 1 μg ml-1, respectively.No interference was observed from the additives that are present in the pharmaceutical formulation or from hydrochlorothiazide and amlodipine that are co-formulated with OLM in some formulations.The assay described herein has great practical value in the routine analysis of OLM in quality control laboratories, as it has high throughput property, consumes minimum volume of organic solvent thus it offers the reduction in the exposures of the analysts to the toxic effects of organic solvents, and reduction in the analysis cost by 50-fold.

View Article: PubMed Central - HTML - PubMed

Affiliation: Department of Pharmaceutical Chemistry, College of Pharmacy, King Saud University, P,O, Box 2457, Riyadh 11451, Saudi Arabia. idarwish@ksu.edu.sa.

ABSTRACT
A novel 96-microwell-based spectrophotometric assay has been developed and validated for determination of olmesartan medoxomil (OLM) in tablets. The formation of a colored charge-transfer (CT) complex between OLM as a n-electron donor and 2, 5-dichloro-3, 6-dihydroxy-1, 4-benzoquinone (p-chloranilic acid, pCA) as a π-electron acceptor was investigated, for the first time, and employed as a basis in the development of the proposed assay. The proposed assay was carried out in 96-microwell plates. The absorbance of the colored-CT complex was measured at 490 nm by microwell-plate absorbance reader. The optimum conditions of the reaction and the analytical procedures of the assay were established. Under the optimum conditions, linear relationship with good correlation coefficient was found between the absorbance and the concentration of OLM in the range of 1-200 μg ml-1. The limits of detection and quantitation were 0.3 and 1 μg ml-1, respectively. No interference was observed from the additives that are present in the pharmaceutical formulation or from hydrochlorothiazide and amlodipine that are co-formulated with OLM in some formulations. The assay was successfully applied to the analysis of OLM in tablets with good accuracy and precision. The assay described herein has great practical value in the routine analysis of OLM in quality control laboratories, as it has high throughput property, consumes minimum volume of organic solvent thus it offers the reduction in the exposures of the analysts to the toxic effects of organic solvents, and reduction in the analysis cost by 50-fold. Although the proposed assay was validated for OLM, however, the same methodology could be used for any electron-donating analyte for which a CT reaction can be performed.

No MeSH data available.


Related in: MedlinePlus

The chemical structure of olmesartan medoxomil (OLM) and the co-formulated drugs.
© Copyright Policy
Related In: Results  -  Collection


getmorefigures.php?uid=PMC3275517&req=5

Figure 1: The chemical structure of olmesartan medoxomil (OLM) and the co-formulated drugs.

Mentions: Olmesartan medoxomil (OLM); (5-methyl-2-oxo-2H-1,3-dioxol-4-yl)methyl 4-(2-hydroxy-propan-2-yl)-2-propyl-1-({4-[2-(2H-1,2,3,4-tetrazol-5-yl)phenyl]phenyl}methyl)-1H-imidazole-5-carboxylate (Figure 1), is the newest member of non-peptide angiotensin II receptor antagonists used worldwide in the treatment of hypertension. It is an ester prodrug, which is completely and rapidly hydrolyzed to the active acid form, olmesartan. OLM exerts its action mainly via a selective blockade action on AT1 receptors and the consequent reduced pressor effect of angiotensin II [1,2]. OLM may be used alone or in combination with other antihypertensive agents. The FDA has determined that the benefits of OLM continue to outweigh its potential risks when used for the treatment of patients with high blood pressure according to the drug label. OLM is also used by some people who are treated with an unproven therapy for autoimmune diseases known as the Marshall Protocol.


Development of a novel 96-microwell assay with high throughput for determination of olmesartan medoxomil in its tablets.

Darwish IA, Wani TA, Khalil NY, Al-Shaikh AA, Al-Morshadi N - Chem Cent J (2012)

The chemical structure of olmesartan medoxomil (OLM) and the co-formulated drugs.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3275517&req=5

Figure 1: The chemical structure of olmesartan medoxomil (OLM) and the co-formulated drugs.
Mentions: Olmesartan medoxomil (OLM); (5-methyl-2-oxo-2H-1,3-dioxol-4-yl)methyl 4-(2-hydroxy-propan-2-yl)-2-propyl-1-({4-[2-(2H-1,2,3,4-tetrazol-5-yl)phenyl]phenyl}methyl)-1H-imidazole-5-carboxylate (Figure 1), is the newest member of non-peptide angiotensin II receptor antagonists used worldwide in the treatment of hypertension. It is an ester prodrug, which is completely and rapidly hydrolyzed to the active acid form, olmesartan. OLM exerts its action mainly via a selective blockade action on AT1 receptors and the consequent reduced pressor effect of angiotensin II [1,2]. OLM may be used alone or in combination with other antihypertensive agents. The FDA has determined that the benefits of OLM continue to outweigh its potential risks when used for the treatment of patients with high blood pressure according to the drug label. OLM is also used by some people who are treated with an unproven therapy for autoimmune diseases known as the Marshall Protocol.

Bottom Line: The limits of detection and quantitation were 0.3 and 1 μg ml-1, respectively.No interference was observed from the additives that are present in the pharmaceutical formulation or from hydrochlorothiazide and amlodipine that are co-formulated with OLM in some formulations.The assay described herein has great practical value in the routine analysis of OLM in quality control laboratories, as it has high throughput property, consumes minimum volume of organic solvent thus it offers the reduction in the exposures of the analysts to the toxic effects of organic solvents, and reduction in the analysis cost by 50-fold.

View Article: PubMed Central - HTML - PubMed

Affiliation: Department of Pharmaceutical Chemistry, College of Pharmacy, King Saud University, P,O, Box 2457, Riyadh 11451, Saudi Arabia. idarwish@ksu.edu.sa.

ABSTRACT
A novel 96-microwell-based spectrophotometric assay has been developed and validated for determination of olmesartan medoxomil (OLM) in tablets. The formation of a colored charge-transfer (CT) complex between OLM as a n-electron donor and 2, 5-dichloro-3, 6-dihydroxy-1, 4-benzoquinone (p-chloranilic acid, pCA) as a π-electron acceptor was investigated, for the first time, and employed as a basis in the development of the proposed assay. The proposed assay was carried out in 96-microwell plates. The absorbance of the colored-CT complex was measured at 490 nm by microwell-plate absorbance reader. The optimum conditions of the reaction and the analytical procedures of the assay were established. Under the optimum conditions, linear relationship with good correlation coefficient was found between the absorbance and the concentration of OLM in the range of 1-200 μg ml-1. The limits of detection and quantitation were 0.3 and 1 μg ml-1, respectively. No interference was observed from the additives that are present in the pharmaceutical formulation or from hydrochlorothiazide and amlodipine that are co-formulated with OLM in some formulations. The assay was successfully applied to the analysis of OLM in tablets with good accuracy and precision. The assay described herein has great practical value in the routine analysis of OLM in quality control laboratories, as it has high throughput property, consumes minimum volume of organic solvent thus it offers the reduction in the exposures of the analysts to the toxic effects of organic solvents, and reduction in the analysis cost by 50-fold. Although the proposed assay was validated for OLM, however, the same methodology could be used for any electron-donating analyte for which a CT reaction can be performed.

No MeSH data available.


Related in: MedlinePlus