Table 4. Stability of the 9 analytes in mice brain (n=3).

Analytes	Concentration (ng/mL)	24 h, room temperature		30 days, −20°C		3 freeze-thaw cycles		8 h, 4°C
		RE (%)	RSD (%)	RE (%)	RSD (%)	RE (%)	RSD (%)	RE (%)	RSD (%)
GABA	10	8.2	6.3	−2.9	3.6	−5.3	5.8	3.9	10.2
	150	−7.2	2.9	1.8	4.9	5.2	3.4	−4.1	4.4
	800	7.2	4.2	−4.1	3.8	−3.8	7.9	−5.8	2.2
Glu	20	6.9	5.2	11.2	1.5	8.1	6.2	8.1	4.1
	300	−4.1	3.8	−6.1	4.5	−4.8	2.7	−3.5	8.2
	1600	−2.8	9.3	2.1	6.2	3.7	6.2	−2.4	6.1
NE	20	−4.4	2.3	5.7	3.8	−11.5	7.9	−3.9	5.5
	300	13.7	11.2	8.4	2.7	−4.1	6.2	−8.3	3.0
	1600	3.2	3.5	2.1	7.7	−7.8	4.3	3.4	4.8
DA	5.0	4.3	3.7	−7.2	2.9	−1.9	6.3	5.2	2.2
	750	5.3	5.6	7.2	4.2	4.5	3.3	−6.5	3.3
	400	2.7	4.3	8.7	6.2	4.2	9.3	7.2	5.2
5-HT	5.0	4.2	4.2	3.7	7.2	1.9	3.3	−5.5	7.2
	750	−4.1	4.4	−3.4	2.2	−6.7	4.6	−7.7	2.4
	400	−4.9	2.5	−10.4	2.2	−7.2	2.9	−2.9	2.6
5-HIAA	5.0	4.6	4.2	4.5	8.2	6.2	6.3	−10.4	5.0
	750	1.7	4.8	10.4	3.7	5.1	2.7	5.3	5.6
	400	−6.2	2.1	3.2	3.7	3.8	10.8	7.2	5.2
ACh	5.0	10.2	6.3	7.5	3.2	−10.4	8.7	−8.4	10.0
	750	−2.2	1.9	4.1	8.8	4.1	6.7	2.1	4.6
	400	5.0	2.2	1.9	2.3	4.8	11.8	8.1	3.2
DOPAC	5.0	−10.4	13.7	−9.7	8.3	1.9	2.3	−9.3	8.7
	750	−2.7	2.2	−4.4	2.2	−2.7	2.2	−4.7	3.4
	400	2.9	2.2	−2.4	4.2	2.9	2.2	5.0	2.2
HVA	5.0	3.2	5.1	−2.1	4.4	4.1	5.6	−10.4	6.7
	750	7.2	5.2	7.1	1.4	4.4	8.2	−2.7	2.2
	400	−6.5	7.2	4.1	5.1	−2.5	4.1	8.7	7.2