Use of Charge Transfer Complexation Reactions for the Spectrophotometric Determination of Sumatriptan in Pharmaceuticals
Table 2
Regression and analytical parameters.
Parameter
DDQ method
I2 method
, nm
585
375
Beer’s law limits (g mL−1)
4.0–56.0
2.0–28.0
Molar absorptivity (L mol−1 cm−1)
4.77 × 103
9.56 × 103
Sandell sensitivity* (μg cm−2)
0.0620
0.0309
Limit of detection (μg mL−1)
0.77
0.17
Limit of quantification (μg mL−1)
2.32
0.52
Regression equation,
Intercept, ()
−0.0104
0.0198
Slope, ()
0.0170
0.0295
Correlation coefficient ()
0.9997
0.9998
Standard deviation of intercept ()
0.00714
0.00499
Standard deviation of slope ()
0.00021
0.00029
*Limit of determination as the weight in μg per mL of solution, which corresponds to an absorbance of measured in a cuvette of cross-sectional area 1 cm2 and l = 1 cm. **, where is the absorbance, is the intercept, is the slope, and is the concentration in μg mL−1.