Response Surface Optimization of a Rapid Ultrasound-Assisted Extraction Method for Simultaneous Determination of Tetracycline Antibiotics in Manure

Table 5

The related recoveries of TCs in fertilizer samples by proposed method.

TCs	Added (mg/kg)	SM			CM			MIM
		Found (mg/kg)	Recovery (%)	RSD (%)	Found (mg/kg)	Recovery (%)	RSD (%)	Found (mg/kg)	Recovery (%)	RSD (%)
OTC	5	4.09	81.75	2.95	3.65	73.00	0.21	5.75	114.93	0.54
	25	21.41	85.64	4.09	23.37	93.50	3.12	27.06	108.23	2.96
	100	83.61	83.61	0.18	95.09	95.09	0.28	102.09	102.09	1.11
TC	5	3.86	77.12	0.83	3.88	77.61	3.65	5.10	102.00	4.87
	25	21.53	86.1	3.62	24.13	96.51	3.05	26.92	107.69	0.28
	100	80.64	80.64	0.39	90.14	90.14	0.23	103.27	103.27	0.95
CTC	5	4.10	81.95	1.48	3.82	76.30	2.11	4.90	98.09	4.22
	25	25.24	100.97	2.02	21.00	84.02	0.12	25.36	101.44	1.03
	100	85.68	85.68	1.30	82.46	82.46	0.01	102.07	102.07	2.93
DC	5	4.16	83.26	1.25	3.56	71.11	2.97	5.82	116.38	4.94
	25	20.18	80.7	0.57	21.76	87.04	0.25	28.22	112.90	3.88
	100	87.12	87.12	0.74	86.65	86.65	1.40	103.10	103.10	4.38

Note: SM: swine manure; CM: cow manure; MIM: mixture of inorganic fertilizer with manure.