Table 1.

Intra- and interday precision of FEP at different concentrations including LLOQ.

	Intraday (n = 20)		Interday (n = 20)
Drug	Concentration	CV (%)	Concentration	CV(%)
FEP	0.47	4.0
	2.45	4.7	2.08	2.0
	24.09	3.0	21.32	1.9
	43.06	2.2	38.50	2.6
MEM	0.45	2.9
	2.33	4.4	2.29	2.8
	23.08	2.0	23.82	2.6
	37.86	1.9	43.90	2.4
Tazobactam	0.42	2.8
	2.25	4.0	2.06	1.9
	22.54	0.9	21.00	1.9
	37.31	1.3	38.53	1.6
Piperacillin	0.43	3.2
	2.31	4.9	2.05	3.6
	22.81	2.0	20.92	2.6
	39.66	3.3	39.77	4.5

^aThree different spiked QC levels were also tested.