Research Article

Method Development for Simultaneously Determining Indomethacin and Nicotinamide in New Combination in Oral Dosage Formulations and Co-Amorphous Systems Using Three UV Spectrophotometric Techniques

Figure 8

The second-order derivative spectra show a specificity test of 6 different mixtures with 6 ratios containing constant nicotinamide 7.5 μg/mL and series of indomethacin (1) 2.5 (light blue), 3.75, 7.5, 15, 22.5, and (6) 45 (black) μg/mL at 276.5 nm. They give the same signal value at 276.5 nm.