Table 5.

Result of stability studies performed at low quality control (LQC) and high quality control (HQC) levels.

		Auto-sampler stability (24 hours, 10°C)		Freeze-thaw stability (3 cycles)		Bench-top (6 hour)		Short term (1 week)
		LQC	HQC	LQC	HQC	LQC	HQC	LQC	HQC
Δ9-THC	Mean	6.66	75.50	6.43	73.18	6.94	77.18	7.11	72.77
	% Bias	6.61	0.67	2.93	−2.42	11.06	2.90	13.72	−2.97
	% CV	2.44	0.55	2.53	3.91	4.78	1.85	-	3.74
CBD	Mean	6.69	75.51	6.47	73.04	6.68	79.13	6.60	74.85
	% Bias	7.04	0.68	3.48	−2.61	6.92	5.50	5.62	−0.19
	% CV	1.18	1.93	1.22	1.72	2.32	1.85	4.82	3.26
11-OH Δ9-THC	Mean	6.47	77.78	6.36	71.70	6.04	78.51	6.97	82.43
	% Bias	3.47	3.70	1.69	−4.40	−3.34	4.69	11.54	9.91
	% CV	3.65	2.51	1.24	1.28	2.62	2.10	1.06	1.94
Δ9-THC-COOH	Mean	6.84	74.05	6.27	72.14	6.44	76.06	6.72	75.81
	% Bias	9.41	−1.27	0.33	−3.81	2.96	1.42	7.50	1.08
	% CV	5.42	2.56	2.95	1.11	0.91	1.14	0.99	6.13

%Bias calculated as 100×(mean-nominal)/nominal; CV calculated as 100×SD/mean; n=2 LQC-6.25 ng mL⁻¹, HQC-75 ng mL⁻¹