Table 3.

Figures of merit for the DLLME procedure and GC-MS method in determination of 13 PAHs in ultrapure water^a

Regression equation	LRe (ngmL-1)	EFd	r2	LODc (ngmL-1)	LOQb (ngmL-1)	PAHs
y= 2.507$0\mathrm{x}$ +0.6869	0.10-2.80	101.40	0.992	0.03	0.10	Naphthalene
y=1.3637$\mathrm{x}$ +0.0954	0.10-2.80	115.78	0.995	0.03	0.10	Acenaphthene
y=1.3686$\mathrm{x}$ +0.1663	0.10-2.80	115.71	0.997	0.03	0.10	Flourene
y=3.6569$\mathrm{x}$ +0.7157	0.35-2.80	112.86	0.995	0.10	0.35	Phenanthrene
y=3.1554$\mathrm{x}$ +0.3356	0.35-2.80	120.00	0.996	0.10	0.35	Anthracene
y=1.4566$\mathrm{x}$ +0.0772	0.35-2.80	92.86	0.996	0.10	0.35	Pyrene
y=0.7353$\mathrm{x}$ -0.0828	0.35-2.80	121.43	0.987	0.10	0.35	Benzo[a]anthracene
y=0.8012$\mathrm{x}$ +0.0014	0.35-2.80	102.86	0.995	0.10	0.35	chrysene
y=0.5118$\mathrm{x}$ -0.1270	0.35-2.80	120.00	0.983	0.10	0.35	Benzo[b]fluoranthene
y=0.6653$\mathrm{x}$ -0.0660	0.35-2.80	125.71	0.996	0.10	0.35	Benzo[k]fluoranthene
y=0.3071$\mathrm{x}$ -0.0501	0.35-2.80	118.57	0.993	0.10	0.35	Benzo[a]pyrene
y=0.0389$\mathrm{x}$ +0.0038	0.35-2.80	128.57	0.999	0.10	0.35	Dibenz[a,h]anthracene
y=0.0705$\mathrm{x}$ -0.0034	0.35-2.80	101.43	0.999	0.10	0.35	Benzo[ghi]perylene

^a _{Extraction conditions: extraction method, DLLME procedure; ulrapure water sample volume, 10 mL; spiking level, 0.1-2.8 ngmL-1; disperser solvent (acetone) volume, 1000 µL; extraction solvent (chloroform) volume, 500 µL; internal standard (anthracene–d10), 0.7 ngmL-1; centrifugation time and rpm, 3min, 2500, room temperature.}

^b _{LOQ, limit of quantification for a S/N = 9.}

^c _{LOD, limit of detection for a S/N = 3.}

^d _{EF, enrichment factor.}

^e _{LR, linear range.}