Stability-Indicating High-Performance Liquid Chromatographic Determination of Levamisole Hydrochloride in Bulk and Dosage Forms

Table 4

Robustness of the developed method (n = 6) (assay and statistical evaluation).

Parameter	RSD for area for six injections	Theoretical plates no.	Tailing factor	Retention time
Developed method (default)	0.143	11162	1.3	6.210
New column	0.784	14903	1.3	9.532
29% acetonitrile (−1%)	0.409	6556	1.3	7.232
31% acetonitrile (+1%)	0.182	11747	1.2	6.437
Buffer pH 7.8 (−0.2)	0.387	11186	1.4	6.123
Buffer pH 8.2 (+0.2)	0.949	12392	1.2	6.809
Wavelength 210 (−5)	0.3190	12331	1.2	6.183
Wavelength 220 (+5)	0.297	11475	1.2	6.110
Flow rate 1.35 (−0.15)	0.156	13075	1.3	6.884
Flow rate 1.65 (+0.15)	0.126	11450	1.3	5.685