Table 2.
Results obtained by the first derivative method for the determination of linagliptin in its binary mixture with metformin
| λmax of measurements | 311 nm |
| Obedience of Beer’s law | 5-30 μg.ml-1 |
| Regression equation | H311=0.0009 Cμg/ml - 0.0001 |
| Regression coefficient (r2) | 0.9995 |
| LOD μg.ml-1 | 0.77 |
| LOQ μg.ml-1 | 2.34 |
| Sb | 3 × 10-5 |
| Sa | 7.2 × 10-4 |
| Confidence limit of the slope | 0.0009 ± 6.45 × 10-7 |
| Confidence limit of the intercept | -0.0001 ± 3 × 10-9 |
| Standard error of the estimation | 6.3 × 10-4 |
| Results | |
| Drug in laboratory prepared mixture with MET | 100.36 ± 1.17 |
| Drug in combination with MET dosage form (JENTADUETO ®) | 100.36 ± 1.91 |
| Drug added to the mixture | 100.00 ± 1.43 |