RESUMO
An efficient method is provided to detect simultaneously some important veterinary drugs from different classes in highly complex animal tissue matrix.This method using matrix solid-phase dispersion (MSPD) and high performance liquid chromatography (HPLC) with diode array detection (DAD) is developed to effectively determine two fluoroquinolones (enoxacin and lomefloxacin),two sulfonamides (sulfanilamide and sulfamethoxazole) and one tetracycline (tetracycline) simultaneously in porcine tissues.In the process,MSPD methodology was used to treat samples,washed by n-hexane to remove lipid,eluted the analytes with acetonitrile-dichloromethane (1∶1,v/v).Solvent acetonitrile and solvent acetic acid (0.1％) were combined in a gradient.HPLC-DAD analysis of the tissue samples was performed within 15min at a flow rate of 1.0mL/min.The results showed that a recovery at 0.1,0.5 and 1.0 μg/g fortification levels ranged from 80.6％ to 99.2％ with satisfactory relative standard deviations (RSDs) (below 6.1％.n=3) and the limits of quantitation (LOQ) ranged from 7 μg/kg to 34 μg/kg in porcine tissues.Utilization of the method in successfully simultaneous analysis of porcine tissue incurred with veterinary drug multiresidues is described.
RESUMO
A rapid method has been developed based on the sample preparation procedure named as QuEChERS （Quick, Easy, Cheap, Effective, Rugged and Safe）, combined with reversed-phase high performance liquid chromatography with fluorescence detector and C18 column after precolumn derivatization using o-phthalaldehyde and 2-mercaptoethanol to determine dopamine in porcine muscle. Methanol and deionized water （0.1% acetic acid, v/v） with a ratio of 60：40 was used as mobile phase. The flow rate was 0.8 mL/min and dopamine was eluted within 15 min. The linearity range was 0.003-8 μg/mL with r=0.9992. The detection limit for dopamine was 4 μg/kg and the quantification limit was 9 μg/kg. Recovery studies were carried out at 0.1, 0.5 and 1.0 mg/kg fortification levels and the average recoveries obtained ranged from 90.4% to 98.2% with relative standard deviations between 3.5% and 8.1%. The method was found to be suitable for detection of dopamine in animal product tissues at the maximum residue level.
RESUMO
A rapid method has been developed based on the sample preparation procedure named as QuEChERS (Quick,Easy,Cheap,Effective,Rugged and Safe),combined with reversed-phase high performance liquid chromatography with fluorescence detector and C18 column after precolumn derivatization using o-phthalaldehyde and 2-mercaptoethanol to determine dopamine in porcine muscle.Methanol and deionized water (0.1％ acetic acid,v/v) with a ratio of 60∶40 was used as mobile phase.The flow rate was 0.8 mL/min and dopamine was eluted within 15 min.The linearity range was 0.003-8 μg/mL with r=0.9992.The detection limit for dopamine was 4 μg/kg and the quantification limit was 9 μg/kg.Recovery studies were carried out at 0.1,0.5 and 1.0 mg/kg fortification levels and the average recoveries obtained ranged from 90.4％ to 98.2％ with relative standard deviations between 3.5％ and 8.1％.The method was found to be suitable for detection of dopamine in animal product tissues at the maximum residue level.