TABLE 3.

METHOD VALIDATION RESULTS FOR FOUR PRESERVATIVES

Validation steps	Parameters	Results				Acceptance
		PhOE	MP	EP	PP	criteria
Repeatability	RSD (%, n = 6)	0.307	0.097	0.317	0.283	X < 2
Int. precision
Day 1	RSD (%)	0.329	0.130	0.365	0.401	X < 2
Day 2	RSD (%)	0.242	0.165	0.417	0.372	X < 2
Standard stability (48 h data)	Change in response factor (%)	0.13	0.13	0.13	0.15	X < 2
System suitability	RSD (%, n = 6)	0.11	0.15	0.09	0.26	X < 2

RSD: Relative standard deviation.