This work presents an optimization of a quick, easy, cheap, effective, rugged and safe (QuEChERS) extraction approach of eleven fluoroquinolones in poultry muscle and kidney using a 33 Box-Behnken factorial design. All the data treatment was performed using Microsoft Excel® 2010. The suitability of the developed method was confirmed by two proficiency tests for ciprofloxacin and enrofloxacin.
Keywords:
Box-Behnken design; fluoroquinolones; QuEChERS; liquid chromatography; mass spectrometry
| Sum of square | Degree of freedom | |
|---|---|---|
| SSR | (ŷ – ȳ)t t : transposed matrix. – (ŷ – ȳ) (5) | p − 1 |
| RSS | (yij – ŷ)t t : transposed matrix. – (yij – ŷ) (6) | n − p |
| SSEP | (yij – ȳi)t t : transposed matrix. – (yij – ȳi) (7) | n − m |
| SSLF | (ŷ – ȳi)t t : transposed matrix. – (ŷ – ȳi) (8) | m − p |
| Parameter | Sample | Coefficient | Pure error | Confidence limit | |
|---|---|---|---|---|---|
| −95% | 95% | ||||
| b0 | Muscle | 7.37 | 0.09 | 6.99 | 7.74 |
| Kidney | 7.90 | 0.05 | 7.69 | 8.11 | |
| (1) Extraction phase (L) | Muscle | 0.25 | 0.05 | 0.02 | 0.48 |
| Kidney | −0.43 | 0.03 | −0.56 | −0.30 | |
| (2) Acetic acid / % (L) | Muscle | 0.60 | 0.05 | 0.37 | 0.83 |
| Kidney | 0.65 | 0.03 | 0.52 | 0.78 | |
| (3) Sorbent (L) | Muscle | 0.20 | 0.05 | −0.03 | 0.43 |
| Kidney | 0.42 | 0.03 | 0.30 | 0.55 | |
| (1) Extraction phase (Q) | Muscle | 0.16 | 0.08 | −0.18 | 0.50 |
| Kidney | −0.15 | 0.04 | −0.34 | 0.04 | |
| (2) Acetic acid / % (Q) | Muscle | −0.25 | 0.08 | −0.59 | 0.09 |
| Kidney | −0.63 | 0.04 | −0.82 | −0.44 | |
| (3) Sorbent (Q) | Muscle | 0.02 | 0.08 | −0.31 | 0.36 |
| Kidney | −0.04 | 0.04 | −0.23 | 0.15 | |
| (1)*(2) | Muscle | 0.40 | 0.08 | 0.07 | 0.73 |
| Kidney | −0.85 | 0.04 | −1.03 | −0.67 | |
| (1)*(3) | Muscle | 0.12 | 0.08 | −0.21 | 0.44 |
| Kidney | −0.22 | 0.04 | −0.40 | −0.03 | |
| (2)*(3) | Muscle | 0.10 | 0.08 | −0.22 | 0.43 |
| Kidney | −0.14 | 0.04 | −0.32 | 0.05 | |
| Specie | Tissue | Sample | Analyte | Lab's results / (μg g−1) | Assigned value / (μg g−1) | Z-score |
|---|---|---|---|---|---|---|
| Veal | liver | XP1343 | CIP | 0.024 ± 0.002 | 0.021 | 0.65 |
| ENR | 0.000 ± 0.003 | 0.000 | 0.00 | |||
| XP1344 | CIP | 0.028 ± 0.002 | 0.025 | 0.55 | ||
| ENR | 0.019 ± 0.003 | 0.017 | 0.53 | |||
| XP1345 | CIP | 0.014 ± 0.002 | 0.016 | −0.57 | ||
| ENR | 0.034 ± 0.003 | 0.034 | 0.00 | |||
| XP1346 | CIP | 0.000 ± 0.002 | 0.000 | 0.00 | ||
| ENR | 0.000 ± 0.003 | 0.000 | 0.00 | |||
| Equine | kidney | XP1419 | ENR | 0.000 ± 0.003 | 0.000 | 0.00 |
| XP1420 | ENR | 0.000 ± 0.003 | 0.000 | 0.00 | ||
| XP1421 | ENR | 0.042 ± 0.003 | 0.042 | 0.00 | ||
| XP1422 | ENR | 0.016 ± 0.003 | 0.015 | 0.30 |
