Spectrophotometric and Spectrofluorimetric Studies on Azilsartan Medoxomil and Chlorthalidone to Be Utilized in Their Determination in Pharmaceuticals

Abstract

The recently approved angiotensin II receptor blocker, azilsartan medoxomil (AZL), was determined spectrophotometrically and spectrofluorimetrically in its combination with chlorthalidone (CLT) in their combined dosage form. The UV-spectrophotometric technique depends on simultaneous measurement of the first derivative spectra for AZL and CLT at 286 and 257 nm, respectively, in methanol. The spectrofluorimetric technique depends on measurement of the fourth derivative of the synchronous spectra intensities of AZL in presence of CLT at 298 nm in methanol. The effects of different solvents on spectrophotometric and spectrofluorimetric responses were studied. For, the spectrofluorimetric study, the effect of pH and micelle-assisted fluorescence enhancement were also studied. Linearity, accuracy, and precision were found to be satisfactory over the concentration ranges of 8–50 μg mL−1 and 2–20 μg mL−1 for AZL and CLT, respectively, in the spectrophotometric method as well as 0.01–0.08 μg mL−1 for AZL in the spectrofluorimetric method. The methods were successfully applied for the determination of the studied drugs in their co-formulated tablets. The developed methods are inexpensive and simple for the quality control and routine analysis of the cited drugs in bulk and in pharmaceuticals.

Full spectrum and genetic algorithm-selected spectrum-based chemometric methods for simultaneous determination of azilsartan medoxomil, chlorthalidone, and azilsartan: Development, validation, and application on commercial dosage form

“…The standard addition technique was applied to evaluate the validity of the proposed methods ( Table 6). In bulk powder and commercial tablets, the results of the CHT and AZM determination were compared statistically with the reference first derivative spectra method [11] ( Table 7). "F" and "t" values were calculated, and they were found less than the tabulated ones apart from the case of PLS and PCR for CHT and AZM determination in commercial tablets (tand F-test values were higher than tabulated ones in case of AZM, and t value was higher than tabulated one in case of CHT).…”

“…Multivariate statistical models are very useful in spectral analysis because of simultaneous incorporation of multiple spectral intensities, which greatly improve the accuracy and potential applications of quantitative spectral analysis [10]. The literature survey showed that spectroscopic, RP-HPLC, and LC-MS methods [11,12] are reported for quantitation of AZM and CHT binary mixture. However, there is no reported method for the quantitation of the ternary mixture of AZM, CHT, and AZ may be because of the high similarity of UV spectra of AZM and AZ.…”

“…459512) by the proposed multivariate calibration methods and reference method Figures in parentheses are theoretical values for t-and F-tests at confidence level of 95%. bReference first derivative spectra method is that published in the literature(11).…”

Liquid chromatography/tandem mass spectrometry study of forced degradation of azilsartan medoxomil potassium

“…[19] Recently, Ebeid et al have developed a stability-indicating method for the combination of azilsartan medoxomil and chlorthalidone with its subsequent application to degradation kinetics. [20] However, no method has been reported for characterization of the degradation products formed under various stress conditions. Identification and characterization of degradation products is very important in the field of drug development.…”

A novel method to determine new potent angiotensin inhibitor, azilsartan, in human plasma via micelle-enhanced spectrofluorimetry using cremophor RH 40

“…AZL in combination with chlorthalidone was also determined in dosage form using UV and fluorescence spectrophotometry [21], HPLC [22][23][24][25] and in human and rat plasma using LC/MS [26]. Fluorescence spectrometry is a very simple, rapid, efficient, selective, and highly sensitive technique for determination of drug in plasma [27][28][29].…”