Table 1. Analytical Parameters and Variations Applied for Analysis of Robustness.

	parameter	nominal conditions		variations
A/a	mobile flow rate	0.3 mL/min	A	0.5 mL/min	a
B/b	column temperature	30 °C	B	32 °C	b
C/c	mobile phase (A/B)	25:75	C	30:70	c
D/d	Ortho-phosphoric acid concentration in solvent B	0.01%	D	0.02%	d
E/e	wavelength	271	E	260	e
		371		360