Research Article
Different Spectrophotometric Methods for Simultaneous Determination of Trelagliptin and Its Acid Degradation Product
Table 2
Results obtained by the proposed first-derivative spectrophotometric method for determination of TRG and TAD.
| | Item | TRG at 260.4 nm | TAD at 274 nm |
| | Range of linearity (μg/mL) | 5–50 | 2.5–25 | | Regression equation | A = 0.0067 C·μg/mL–0.0008 | A = 0.0288 C·μg/mL–0.0094 | | Regression coefficient (r) | 0.9998 | 0.9997 | | LOD (μg/mL) | 1.21 | 0.77 | | LOQ (μg/mL) | 3.67 | 2.34 | | 6.31 × 10−5 | 5.41 × 10−4 | | 0.002 | 0.006 | | Confidence limit of the slope | 0.0067 ± 4.23 × 10−7 | 0.0288 ± 9.93 × 10−6 | | Confidence limit of the intercept | −0.0008 ± 1.87 × 10−6 | −0.0094 ± 6.05 × 10−5 | | Standard error of the estimation | 0.002 | 0.006 | Accuracy
Laboratory prepared (mean ± SD) | 99.43 ± 0.78 | 99.31 ± 0.45 | | Standard addition (mean ± SD) | 99.51 ± 1.36 | | Precision
Intraday % RSD | 0.45–0.53–0.71 | 0.43–0.51–0.64 | | Interday % RSD | 0.28–0.41–0.51 | 0.27–0.39–0.46 | | Drug in dosage form (mean ± SD) | 99.37 ± 0.89 | |
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Standard deviations of the slope Sb & intercept Sa. |
