Spectrofluorimetric determination of α-difluoromethylornithine through condensation with ninhydrin and phenylacetaldehyde: application to pharmaceutical cream and spiked urine samples

α-difluoromethylornithine (DFMO) is an anti-Trypanosoma Brucei agent that is approved for the medication of sleeping sickness and is widely licensed for the treatment and diminishing the unwanted facial hair (hirsutism). The suggested work provides a comprehensive analytical protocol for investigating the fluorescence properties of the reaction product between DFMO and ninhydrin/phenylacetaldehyde reagent. In this approach, all reaction conditions such as reagent volumes, buffer volume, pH value, heating time and heating temperature were carefully handled and optimized. The formed product was measured spectrofluorimetrically at the emission wavelength of 483 nm upon its excitation at the wavelength of 388 nm. For accuracy, linearity, sensitivity, robustness and preciseness of the method, the suggested approach was validated and verified according to ICH guiding principles. Also, the proposed work offered a unique selectivity for the determination of DFMO with agreeable recovery values in different brands of commercial cream samples without interference from cream excipients. Lastly, the suggested approach was assured to be successful in the estimation of DFMO in human urine specimens with agreeable recovery results.