Simple and Selective Spectrophotometric Determination of Ofloxacin in Pharmaceutical Formulations Using Two Sulphonphthalein Acid Dyes
Table 2
Sensitivity and regression parameters.
Parameter
Method A
Method B
, nm
400
410
Linear range, μg/mL
1.0–16.0
1.0–16.0
Molar absorptivity (ε), L /mol/cm
2.40 × 104
1.96 × 104
Sandell’s sensitivity*, μg/cm2
0.015
0.019
Limit of detection (LOD), μg/mL
0.11
0.09
Limit of quantification (LOQ), μg/mL
0.32
0.27
Regression equation,
Intercept ()
0.003
0.012
Slope ()
0.061
0.051
Standard deviation of ()
0.126
0.040
Standard deviation of ()
0.008
0.003
Regression coefficient ()
0.999
0.999
Limit of determination as the weight in μg per mL of solution, which corresponds to an absorbance of = 0.001 measured in a cuvette of cross-sectional area 1 cm2 and = 1 cm. **, where is the absorbance, is concentration in μg/mL, is intercept, and is slope.