Drug substance The proposed UPLC Authentic sample Derivative synchronous spectroscopy FDSFS Reference methodb Meana ±a SD 98.55 ± 0.78 98.32 ± 0.66 99.72 ± 1.32 t-test 1.77 2.18 2.23c F-value 2.86 4.00 6.2c aMean of seven and five determination of the proposed and reference methods. bAn HPLC method using a cyano column with gradient flow and two mobile phase components :(component A) methanol: buffer (3:17 v/v), (component B) methanol : buffer (3:1 v/v), UV detection at 210 nm (24) cThe theoretical values of t and F at P=0.05

Table 4: Statistical comparison between the proposed and the reference method for the determination of atomoxetine HCl in drug substance.