The –NO2 vibrational spectra of metronidazole for analytical method development using Fourier Transform Infrared compared to the UV-VIS spectrophotometry

Abstract

This study aimed to develop a green method in analyzing metronidazole compound using Fourier Transform Infrared (FTIR) and to ensure that this method is suitable to be done for tablet content determination, and then was compared to the established spectrophotometry ultraviolet-Visible (UV-Vis). Both methods were compared in terms of analysis parameters, effectiveness, and cost required. The experiment was started by screening to find the best spectra was performed, supported by derivation mode to increase the specificity. After that, the method was developed by tests its validation parameters, and then it was applied for tablet content determination. All observation results were compared to an established spectrophotometry UV-VISVis, which also has been verified concurrently. As a result, metronidazole showed a specific spectrum of -NO2 at 1388.5-1338.36 cm-1, which is not interfered by matrices. The calibration curve yielded revealed the correlation regression (r) = 0.99985. All validation parameter requirements can be fulfilled by this method, which had the limit of detection and limit of quantification of 0.36 ppm and 1.19 ppm, respectively. As the comparison to UVVis spectrophotometry, in terms of effectiveness, the FTIR method is relatively more practical and more straightforward, it was evidenced by the shorter processing time than the counterpart. In terms of cost, the FTIR method also required a relatively less cost. Besides, it is more environmentally friendly due to the absence of solvent usage.