Table 3.

Intra-day and Inter-day accuracy and precisions of GA and GABA calibration standards.

Combined Intra-Day and Inter-Day Accuracy and Precision
GA					GABA
Conc.	Measured Conc.	SD	% Error	% CV	Conc.	Measured Conc.	SD	% Error	% CV
0.5	0.5	0.02	−3.3	3.2	0.5	0.5	0.02	0.0	3.5
2.5	2.5	0.18	−1.6	7.4	2.5	2.5	0.03	1.2	1.2
5	4.8	0.22	−3.3	4.6	5	4.9	0.03	−1.8	0.7
10	10.8	0.21	7.8	2.0	10	10.4	0.33	4.2	3.1
25	25.9	1.07	3.9	4.1	25	23.7	0.20	−5.2	0.8
50	47.4	1.51	−5.2	3.2	50	51.3	0.36	2.7	0.7
100	101.1	0.59	1.1	0.6	100	97.9	2.69	−2.1	2.7
Instrument Precision and Derivatization Reproducibility
GA					GABA
Conc.	Measured Conc.	SD	% Error	% CV	Conc.	Measured Conc.	SD	% Error	% CV
25	25.4	1.59	1.4	6.3	25	24.1	0.3	−3.7	1.4