Studies On Method Of Determination Of Chloramphenicol Residues And Its Elimination In Tissues Of Chickens

Chloramphenicol (CAP) was a high-effective broad-spectrum antibiotics used inanimals. But it has been found that CAP residues in animal tissues and/or animal productshad toxic effects to human body. Therefore, it was necessary to study an analytical methodfor the elimination of monitoring CAP residues in tissues of chickens. A high-performance-liquid-chromatography(HPLC)method for measuring CAPresidues in tissues of chickens was established. CAP residues were extracted and purifiedby acetonitrile, ethyl acetate, and n-hexane from the plasma, muscle and liver, and thenredissolved by mobile phase (acetonitrile: water , 20:80) or 20% acetonitrile solutionrespectively at 1ml/min flow rate and 40℃. Detection wave length of UV was set 278nm.Under the above conditions, the detection limit of CAP in tissues was 0.01μg/ml. Thecalibration curve was linear in the range of 0.01～40μg/ml. At 0.05, 0.5, 5, 20μg/mlconcentration, the CV% within day was 3.74%, 1.79%, 1.20%, 0.71% for plasma , 3.45%,1.82%, 1.47%, 0.92% for muscle and 3.96%, 2.39%, 1.61%, 0.87% for liver respectively;the between day CV% was 4.83%, 3.77%, 2.54%, 1.78% for plasma, 4.54%, 3.50%, 2.39%,1.23% for muscle and 5.07%, 3.63%, 2.77%, 1.53% for liver respectively. The recoveriesof CAP added to the plasma, muscle and liver at levels of 0.05, 0.5, 5, 20μg/ml were83.98%±3.69%, 85.23%±2.68%, 84.71%±3.11%, 85.63%±1.57% from plasma,85.83%±3.15%, 87.69%±2.91%, 88.62%±2.10%, 87.41%±2.87% from muscle,84.56% ± 2.95%, 88.12% ± 2.74%, 85.38% ± 1.76%, 87.96% ± 2.37% from liverrespectively . The results showed this method was sensitive and reliable to measuring CAPresidues in tissues of chickens. The elimination characteristics of single-dose administration (30mg/kg)can bedescribed by the equations as follows: C_blood=13.829e^-0.1505t , C_muscle=44.478e^-0.0945tC_liver=41.946e^-0.0814t. According to the equations , the time taken by the concentrations ofChloramphenicol dropping to 0.01μg/ml in blood, muscle and liver was48.06,88.89,102.48 hours respectively.