Parameters Dual wavelength method Q-analysis method MCR method EXRSM
ALP BENZ ALP BENZ ALP BENZ ALP BENZ
λ(nm) Difference in absorbance      between 253 & 274.4 nm Difference in absorbance      between 238.2 & 261.2 nm 245.8 nm(λiso) and 250(λmax) Peak amplitudes(233.4 & 257.4 nm) Peak amplitudes(228.4 & 252.6 nm) 250 nm(λmax) 238 nm(λmax)
Beer’s law range 5-60 µgml-1 5-20 µgml-1 5-60 µgml-1 5-20 µgml-1 5-50 µgml-1 5-25 µgml-1 5-50 µgml-1 5-20 µgml-1
Regression equation Y=0.0368x-0.0126 Y=0.0438x-0.1063 C=(Qm-0.8055/1.0639-0.8055)× A/0.0484 C=(Qm-1.0639/0.8055-1.0639)× A/0.0457 Y=0.0591x-0.0004 Y=0.1535x-0.2765 Y=0.0517x-0.0064 Y=0.0664x-0.0967
Correlation coefficient 0.9999 0.9998 -- -- 0.9999 0.9999 0.9998 0.9999
Accuracy 99.75 99.67 99.34 99.72 99.88 100.04 99.11 100.03
Precision                
Repeatability 1.293 1.286 1.463 0.924 1.317 0.727 0.753 0.598
Intermediate precision 0.528 1.050 1.092 1.199 0.433 0.551 0.513 0.286
Table 1: Linear regression and analytical parameters of the proposed methods for determination of Allopurinol and Benzbromarone.