Table 2.

Precision and accuracy of the method (n = 6).

Analyte	Spiked conc. (μg/mL)	Intrabatch (n = 6)			Interbatch (n = 3)
		Measured conc.a (μg/mL)	Accuracy (%)	Precision RSD (%)	Measured conc.a (μg/mL)	Accuracy (%)	Precision RSD (%)
5-HTP	0.10	0.10 ± 0.00	96.32	0.52	0.10 ± 0.00	95.12	4.23
	0.42	0.41 ± 0.01	97.62	1.35	0.41 ± 0.02	96.53	4.88
	1.50	1.44 ± 0.02	96.17	1.39	1.46 ± 0.04	97.33	2.74
5-HIAA	0.10	0.10 ± 0.00	98.20	2.24	0.10 ± 0.00	97.03	2.83
	0.42	0.40 ± 0.01	95.24	2.38	0.41 ± 0.02	97.62	4.88
	1.50	1.48 ± 0.02	98.67	1.35	1.46 ± 0.03	97.33	2.05
5-HT	0.10	0.10 ± 0.00	98.78	1.55	0.10 ± 0.00	96.64	3.66
	0.42	0.41 ± 0.02	97.62	4.88	0.44 ± 0.02	104.76	4.55
	1.50	1.50 ± 0.02	99.87	1.33	1.53 ± 0.07	102.00	4.58
L-Glu	2.50	2.47 ± 0.03	98.80	1.21	2.42 ± 0.08	96.80	3.31
	16.00	15.96 ± 0.08	99.75	0.50	15.67 ± 0.22	97.94	1.40
	240.00	234.92 ± 0.87	97.88	0.37	234.08 ± 5.21	97.53	2.23
L-Asp	2.50	2.44 ± 0.01	97.60	0.41	2.43 ± 0.06	97.20	2.45
	16.00	15.39 ± 0.04	96.19	0.26	15.50 ± 0.11	96.88	0.71
	240.00	237.43 ± 0.88	98.93	0.37	248.21 ± 1.35	103.42	0.54

Conc. = concentration; 5-HIAA = 5-hydroxyindoleacetic acid; 5-HT = 5-hydroxytryptamine; 5-HTP = 5-hydroxytryptophan; L-Asp = aspartate; L-Glu = glutamate: RSD = relative standard deviation.

^aData expressed as mean ± standard deviation unless otherwise indicated.