Second derivative spectrophotometric determination of trimethoprime and sulfamethoxazole in the presence of hydroxypropyl-B-cyclodextrin (HP-B-CD)

GLADYS GRANERO; CLAUDIA GARNERO; MARCELA LONGHI

JOURNAL OF PHARMACEUTICAL AND BIOMEDICAL ANALYSIS

ELSEVIER

Año: 2002 vol. 29 p. 51 - 59

0731-7085

An easy and rapid second-derivative spectrophotometric method for the simultaneous analysis of trimethoprime (TMP) and sulfamethoxazole (SM) is described. These drugs have been used as antibacterial against a wide spectrum of organisms and combinations of these drugs are commonly used for the treatment of a variety of infections. The most advantageous approach of this method is the use of HP-b-CD, which allows to improve the performance of the second-derivative ultraviolet spectrophotometry. For both compounds, a shift of the absorption bands and variations of their intensity were observed. The calibration graphs were linear in the concentration range of TMP (1.92–19.2 g ml−1) and SM (1.60–16.5 g ml−1), the correlation coefficient for the calibration graphs was better than 0.9994 and the precision was satisfactory (CV% 4.96) in HP-b-CD solutions. The proposed method was succesfully applied to the assay of commercial tablets. The results were compared to those obtained by second-derivative ultraviolet spectrophotometry in the absence of HP-b-CD. Thereby, the details of the statistical treatment of the analytical data are also presented. © 2002 Elsevier Science B.V. All rights reserved.b-CD, which allows to improve the performance of the second-derivative ultraviolet spectrophotometry. For both compounds, a shift of the absorption bands and variations of their intensity were observed. The calibration graphs were linear in the concentration range of TMP (1.92–19.2 g ml−1) and SM (1.60–16.5 g ml−1), the correlation coefficient for the calibration graphs was better than 0.9994 and the precision was satisfactory (CV% 4.96) in HP-b-CD solutions. The proposed method was succesfully applied to the assay of commercial tablets. The results were compared to those obtained by second-derivative ultraviolet spectrophotometry in the absence of HP-b-CD. Thereby, the details of the statistical treatment of the analytical data are also presented. © 2002 Elsevier Science B.V. All rights reserved. Keywords: Antibacterial drugs; Hydroxypropyl-b-cyclodextrin; Second-derivative ultraviolet spectrophotometry; Inclusion complexes; Validation: Antibacterial drugs; Hydroxypropyl-b-cyclodextrin; Second-derivative ultraviolet spectrophotometry; Inclusion complexes; Validation