Green spectrofluorimetric methods for tramadol assay with ibuprofen or chlorzoxazone: comparison of greenness profiles.

At this time, green analytical chemistry is gaining more interest and concern. The present work details three green spectrofluorimetric methods for tramadol (TRM) determination using ibuprofen (IBU) (mixture 1) and chlorzoxazone (CLZ) (mixture 2). In first method, two excitation wavelengths (λ ), 220 and 280 nm, were used to record the emission spectra for IBU and TRM, respectively (mixture 1) followed by a first derivative treatment. For mixture 2, one λ (280 nm) was optimum for both drugs followed by a first derivative technique for TRM and a second derivative for CLZ determinations. The second method measured the first derivative values for synchronous spectra using constant-wavelength mode at 280 nm for TRM and 260 nm for IBU, and at 270 nm for TRM and 292 nm for CLZ. The third method used constant-energy mode to record synchronous spectra. First derivative values were computed at 282 nm for TRM and 260 nm for IBU in mixture 1 and at 272 nm for TRM and 292 nm for CLZ in mixture 2. ICH validation guidelines were assessed in full and assay of the two TRM binary mixtures in their drug products was successful. Green profile evaluation for the developed methods compared with the reported chromatographic methods was performed using the 'analytical eco-scale' and the 'green analytical procedure index'. These two assessment tools corroborated that the proposed methods achieved the most green parameters, therefore recommending their use as a green option for analyzing the studied drugs in bulk and dosage forms for routine quality control.