Application of two charge transfer complex formation reactions for selective determination of metformin hydrochloride in pharmaceuticals and urine

Future Journal of Pharmaceutical Sciences

Table 3 Results of study of repeatability and intermediate accuracies and precisions of proposed methods

Method	MEB taken, μg mL^-1	Within-day accuracy and precision (n = 7)			Inter-day accuracy and precision (n = 5)
Method	MEB taken, μg mL^-1	MEB found, μg mL^-1	%RE	%RSD	MEB found, μg mL^-1	%RE	%RSD
PCA method	160.0	158.9	0.68	0.54	161.2	0.75	1.75
	200.0	202.1	1.05	0.72	202.3	1.15	0.96
	240.0	244.7	1.96	0.95	244.9	2.04	1.34
DDQ method	32.0	31.4	1.87	1.13	31.3	2.18	1.34
	40.0	39.7	0.75	0.67	39.6	1.00	0.78
	48.0	48.3	0.62	0.82	48.4	0.83	1.09