Table 5.

Stability study of analytes in spiked saliva stored in a fridge at 8 °C and after freeze–thaw cycles at −21 °C. The stability of the extracts kept in the autosampler at 15 °C for 72 h. Values in the table are expressed as %loss.

Analyte	−21 °C			8 °C			15 °C
	30	2000	3750	30	2000	3750	30	2000	3750
	Difference (%)
Carbamazepine	−2.25	−2.16	−1.44	−3.91	−2.53	−1.93	−0.30	−1.12	−1.72
Carbamazepine-10,11 epoxide	−2.45	−1.92	−0.48	−6.23	−3.56	−2.75	−3.64	−2.3	0.38