Analytical quality by design approach to RP-HPLC method development and validation for simultaneous estimation of esomeprazole and naproxen in modified-release dosage form

Future Journal of Pharmaceutical Sciences

Table 9 Effects of robustness study of ESP and NAP under different altered conditions

Parameter	Theoretical variance	Actual variance	% RSD of RT for NAP	% RSD of peak area for NAP	% RSD of RT for ESP	% RSD of peak area for ESP
Elution ratio of organic	± 2.0% of the set ratio	48% v/v	0.20	0.13	0.13	0.69
Elution ratio of organic	± 2.0% of the set ratio	52% v/v	0.45	0.14	0.26	0.75
Column oven temperature	± 2 °C of the set temperature	28 °C	0.11	0.06	0.08	0.64
Column oven temperature	± 2 °C of the set temperature	32 °C	0.25	0.21	0.18	0.31
Flow rate	± 10% of the set flow	1.35 ml/min	0.28	0.06	0.28	0.71
Flow rate	± 10% of the set flow	1.65 ml/min	1.33	0.80	1.25	1.34