Table 2.

Retention time (RT), regression coefficient (r) of the calibration curve, recovery %, intra-day and inter-day precision (%RSD), limit of detection (LOD), and limit of quantification (LOQ) of aromatic amines under optimized LLE and LC-MS/MS conditions.

S. No	Analyte	RT (min)	Regression coefficient (r)	5 ng/mL; n=3			10 ng/mL; n=3			20 ng/mL; n=3			LOD (ng/mL)	LOQ (ng/mL)
				Recovery %	%RSD		Recovery %	%RSD		Recovery %	%RSD
					Intra-day	Inter-day		Intra-day	Inter-day		Intra-day	Inter-day
1	Aniline	2.07	0.9999	95.4	2.16	2.78	91.2	3.89	2.88	92.4	2.54	3.12	0.100	0.2
2	2-NA	5.13	0.9997	94.6	1.59	2.15	95.5	5.96	4.61	93.1	2.12	2.89	0.025	0.1
3	p-Anisidine	2.97	0.9991	96.4	3.46	4.29	93.9	4.18	6.19	101	4.67	5.14	0.050	0.1
4	o-Anisidine	3.21	0.9993	99.1	2.14	2.96	109	8.21	5.04	105	4.23	3.48	0.025	0.1
5	2,4-DMA	4.17	0.9992	109	4.43	3.73	113	3.39	4.18	99.8	4.28	6.03	0.050	0.1
6	2,6-DMA	4.47	0.9998	93.9	5.42	5.27	104	4.50	2.99	98.3	4.67	4.78	0.050	0.1
7	P-CD	4.19	0.9995	110	4.38	3.87	105	6.16	5.95	113	8.49	10.3	0.025	0.1
8	5-NTD	6.36	0.9995	54.9	7.60	9.20	61.0	8.22	11.3	58.2	6.10	9.89	0.500	1.0
9	p-TD	3.31	0.9992	101	3.68	5.20	101	6.12	6.90	108	7.80	7.96	0.025	0.1
10	o/m-TD	3.14	0.9990	103	3.26	3.30	107	5.86	3.44	109	5.51	4.60	0.050	0.1
11	4-CA	4.00	0.9996	105	6.96	7.26	107	5.65	6.09	114	3.43	4.11	0.050	0.1
12	3-CA	4.84	0.9995	78.4	5.04	4.37	80.6	3.95	6.43	81.3	4.56	9.98	0.050	0.1
13	2,4,5-TMA	4.94	0.9997	86.6	3.58	2.17	82.6	3.74	3.29	84.9	7.07	7.38	0.050	0.1
14	2,4,6-TMA	5.11	0.9999	100	2.48	2.23	99.1	6.41	3.14	101	8.35	8.35	0.050	0.2
15	3,3'-DMBD	4.32	0.9993	84.8	7.40	6.03	99.5	4.60	6.64	103	5.16	9.44	0.050	0.2
16	4-EA	3.89	0.9995	92.7	7.95	4.81	111	5.11	4.51	103	5.92	7.03	0.025	0.1
17	3,4-DCA	6.72	0.9991	105	4.56	4.08	114	3.45	2.84	115	3.46	5.11	0.100	0.2
18	1,3-PLD	1.29	0.9992	75.5	4.50	5.50	85.3	4.90	5.64	82.2	5.20	5.40	0.200	0.5
19	4-CTD	5.27	0.9999	85.9	11.7	7.36	95.9	3.60	5.74	83.2	8.89	11.1	0.025	0.1
20	4,4'-OD	2.55	0.9997	71.6	3.43	4.50	79.4	11.1	7.57	78.5	7.22	9.93	0.020	0.1
21	4-AA	1.59	0.9997	108	4.50	4.54	102	2.40	4.95	105	5.43	6.15	0.100	0.2
22	4,4'-MTD	4.11	0.9995	80.7	2.41	2.78	86.4	4.88	4.86	82.8	5.91	6.85	0.025	0.1
23	4,4'-MBCA	8.34	0.9998	75.6	5.60	6.20	81.4	7.57	11.4	79.9	4.60	5.42	0.100	0.2
24	2-ABP	7.20	0.9993	83.0	5.19	8.18	82.2	5.97	6.71	84.6	5.08	7.21	0.050	0.2
25	4-ABP	6.42	0.9995	97.1	3.67	5.88	94.0	6.03	4.61	96.2	6.68	8.57	0.050	0.2
26	BD	3.12	0.9996	94.6	3.43	3.31	98.7	8.85	6.26	103	5.35	7.47	0.050	0.1
27	o-DAD	4.37	0.9995	62.8	7.69	10.4	64.8	9.52	5.44	63.4	10.97	13.8	0.025	0.1
28	4,4'-TD	5.04	0.9996	74.0	5.84	8.83	72.5	5.90	6.68	73.8	10.60	11.3	0.025	0.1
29	4,4'-MDA	2.99	0.9996	96.2	4.81	2.74	94.9	3.80	2.89	92.9	7.10	6.32	0.025	0.1
30	3,4-DAT	3.14	0.9995	31.2	5.41	6.89	28.9	3.45	7.29	30.1	5.79	8.15	0.050	0.1
31	2,4 DAT	2.02	0.9997	36.7	4.96	3.89	48.5	2.71	9.70	45.2	5.92	7.89	0.100	0.2
32	2,6-DAT	1.44	0.9997	68.4	4.89	6.78	75.3	5.08	12.0	70.2	9.21	6.78	0.025	0.1
33	3,4 /2,4 -DAAS	4.18	0.9994	100	4.46	2.03	105	8.60	9.81	111	9.91	10.4	0.100	0.2
34	3-3AB-PA	3.64	0.9995	102	3.85	2.19	101	5.20	4.42	112	6.49	9.80	0.025	0.1
35	DMBPDA	3.27	0.9996	99.3	4.13	5.18	94.9	9.66	6.42	104	5.68	6.94	0.025	0.1
36	2-AMoBzT	5.15	0.9995	92.1	5.62	3.97	94.3	6.74	8.74	102	9.02	8.64	0.050	0.1
37	1,1-BPCH	5.77	0.9993	102	3.00	8.17	107	4.06	2.14	109	6.69	10.6	0.025	0.1
38	Nicotine	2.68	0.9991	100	4.89	6.89	109	4.86	3.33	111	5.42	4.12	0.100	0.2
39	Cotinine	3.32	0.9998	82.6	5.66	3.45	91.8	6.39	3.59	92.3	3.78	5.16	0.025	0.1
40	o-AAT	9.15	0.99994	12.0	7.89	11.2	15.8	7.70	15.9	32.3	7.00	5.30	0.025	0.1
41	4-AAB	8.14	0.9994	24.9	11.2	9.58	45.4	6.59	11.8	43.9	7.70	9.48	0.025	0.1