Solid-Phase Extraction and Large-Volume Sample Stacking-Capillary Electrophoresis for Determination of Tetracycline Residues in Milk

Table 2

Regression parameters of calibration: absorbance (mUA) versus TC concentration (µg·L⁻¹).

Analyte	Regression parameters
	Intercept: b0 ± ts (b0)	Slope: b1 + ts (b1)	Correlation coefficient, r	Limit of detection (µg·L^−1)	Linear range (µg·L^−1)
TC	−0.023 ± 0.026	0.337 + 0.013	0.994	19.93	59.79–200
CT	−0.0122 ± 003	0.030 + 0.001	0.991	23.83	71.49–200
OT	0.006 ± 0.022	0.314 + 0.011	0.995	18.60	55.8–200
DT	−0.029 ± 0.033	0.440 + 0.169	0.994	19.45	58.35–200
Analyte	Repeatability, interday (%RSD, n = 3)			Repeatability, intraday (%RSD, n = 3)
	75 µg·L^−1		150 µg·L^−1	75 µg·L^−1	150 µg·L^−1
TC	6.60		4.72	8.64	6.01
CT	9.11		8.61	9.71	9.19
OT	7.02		1.71	9.19	6.22
DT	5.60		3.94	9.35	5.70