Table 3.

Robustness data (mean ± relative standard deviation) expressed as nominal, low, and high values for flow rate, injection volume, column temperature, organic-phase fraction, and pH value of mobile-phase variations

Parameters	Change	Retention time	Capacity factor (k’)	Symmetry	Area	Resolution	Plates (half width), m
Nominal condition		4.055 ± 0.092	0.674 ± 0.225	0.668 ± 0.744	218.63 ± 0.152	15.748 ± 0.497	31,804 ± 1.122
Flow rate, mL/min	(Low) 0.975	4.149 ± 0.158	0.713 ± 0.414	0.671 ± 0293	224.4 ± 0.293	15.838 ± 0.092	32,472 ± 0.091
	(High) 1.025	3.966 ± 0.065	0.637 ± 0.209	0.666 ± 0.551	213.58 ± 0.069	15.652 ± 0.269	31,360 ± 1.226
Injection volume, µL	(Low) 7.5	4.314 ± 0.085	0.780 ± 0.170	0.710 ± 0.928	161.113 ± 0.203	15.352 ± 0.419	35,811 ± 1.468
	(High) 12.5	4.326 ±0.14	0.785 ± 0.253	0.716 ± 0.293	272.5 ± 0.231	15.166 ± 0.318	34,952 ± 1.673
Temperature, °C	(Low) 24	3.897 ± 0.462	0.612 ± 0.419	0.680 ± 0.365	201.6 ± 0.275	15.173 ± 0.397	31,526 ± 0.306
	(High) 28	3.865 ± 0.076	0.595 ± 0.203	0.688 ± 0.704	202.733 ± 0.138	15.108 ± 0.591	32,442 ± 1.395
Organic phase, %	(Low) 4.9	4.082 ± 0.164	0.685 ± 0.430	0.660 ± 0.606	224.9 ± 0.275	15.807 ± 0.336	30,072 ± 1.328
	(High) 5.1	3.89 ± 0.068	0.605 ± 0.171	0.655 ± 0.648	217.7 ± 0.369	15.493 ± 0.362	29,410 ± 0.134
pH	(Low) 7.3	3.799 ± 0.060	0.568 ± 0.133	0.632 ± 0.527	234.0 ± 0.307	14.139 ± 0.396	27,362 ± 1.247
	(High) 7.5	3.475 ± 0.148	0.434 ± 0.553	0.671 ± 0.523	233.8 ± 0.349	16.391 ± 0.484	28,403 ± 1.974