Spectrophotometric Determination of Zolmitriptan in Bulk Drug and Pharmaceuticals Using Vanillin as a Reagent

Table 3

Robustness and ruggedness.

ZMT taken, μg mL^−1	Robustness		Ruggedness
	Volume of acid^a	Reaction time^b	Interanalysts (%RSD),	Interinstruments (%RSD),
	(𝑛=3)	(𝑛=3)	(𝑛=4)	(𝑛=3)
20.0	1.15	1.78	1.83	1.97
40.0	1.43	2.19	1.64	2.13
60.0	2.01	2.85	1.55	1.89

^aThe volumes of conc. H₂SO₄ solution were 0.9, 1.0, and 1.1 mL; ^breaction times were 9, 10, and 11 min.