Biological Safety Studies and Simultaneous Determination of Linagliptin and Synthetic Impurities by LC-PDA

Table 3

Intraday and interday precision of the analytical method.

	LGT		IMP 1		IMP 2		IMP 3
	%	RSD	%	RSD	%	RSD	%	RSD
Intraday ()
Day 1	99.83	0.73	99.12	3.55	102.39	3.44	100.82	3.45
Day 2	99.57	1.33	99.78	3.00	101.76	4.52	101.31	4.63
Day 3	97.50	1.47	101.63	4.54	102.92	2.06	102.65	2.50
Interday ()	98.97	1.36	100.17	4.14	102.35	3.50	101.59	4.08

LGT: linagliptin; IMP 1: impurity 1; IMP 2: impurity 2; IMP 3: impurity 3; RSD: relative standard deviation.