. Author manuscript; available in PMC: 2016 Sep 14.

Published in final edited form as: Anal Chem. 2015 Oct 5;87(20):10183–10187. doi: 10.1021/acs.analchem.5b02603

Table 1.

Limit of Detection (LOD), Limit of Quantitation (LOQ), Average Extraction Efficiency of Sample Preparation and Average Matrix Effect

	LOD, ng/mL	LOQ, ng/mL	extraction efficiency (“free”/”total”), %			matrix effect (“free”/”total”), %

analyte	“free”/“total”^a	“free”/“total”	low^b	mid	high	low	mid	high
OHTHC	0.008/0.017	0.028/0.048	93/69	81/67	82/75	1.0/13	−5/1	−9/−32
COOH-THC	0.005/0.015	0.018/0.045	83/58	81/60	83/59	5/9	−4/−6	−2/−41
CBD	0.004/0.009	0.012/0.030	88/22	70/26	71/28	8/23	−9/−4	−5/−9
CBN	0.002/0.007	0.008/0.023	76/20	64/18	71/21	2/−6	−8/−16	−4/−12
THC	0.002/0.005	0.008/0.015	74/18	59/19	54/22	6/32	−7/−5	−7/−12

“Free” and “total” refer to unconjugated and the sum of conjugated and unconjugated forms, respectively.

Low, mid and high levels refer to 0.025, 25, and 500 ng/mL, respectively.