Study On The Detection Of Nitrofuran Metabolites Residues In Shrimps

Veterinary drug residue has become a subject of increasing interest for its severe influence on the security of animal-derived food.Veterinary drug residue can cause the increasing bacterial resistance which is harmful to the breeding industry,and it has potential damage to humans through environment and food chain and even directly harmful to humans.Therefore,it is meaningful for public health to strengthen the monitoring of veterinary drug residue.Nitrofurans are one of the most complex and representative residues.It has profound significance to establish an efficient and reliable detection method to assure the food quality and promote the development of aquatic product market in Deqing,one of the important aquaculture bases of shrimps.In this study,an ultra high performance liquid chromatography-tandem quadrupole mass spectrometry(UPLC-MS/MS)method was developed for the determination of nitrofuran residues in shrimps.After optimizing the pre-experimental conditions,nitrofuran residues were extracted from freshwater shrimps,and then nitrofuran derivatives were obtained by the treatment of 2-nitrobenzaldehyde.The quantitative calculation was carried out using internal standard method after multistage calibration.The calibration curve showed a good linearity in the range of 0.5-50 ng/mL with the correlation coefficients larger than 0.999.The limit of detection of nitrofuran metabolites was 0.5 ?g/kg.The average recoveries for spiked samples at concentrations of 0.5 ?g/kg,2.0 ?g/kg,5.0 ?g/kg,10.0 ?g/kg,20.0 ?g/kg ranged from 82.0%to 112.0%with relative standard deviation between 1.23%to 9.80%.More than 200 batches of farmed shrimps obtained from Deqing aquaculture base have been detected.It indicated that detection rate of semicarbazide was 64.0%,with the concentration ranged from 1.59 to 14.85 ?g/kg.The other types of nitrofurans metabolite were not detected.In summary,The UPLC-MS/MS method described here provides a convenient,accurate and reliable protocol for the monitoring of nitrofuran residues.The determination of semicarbazide in shrimp different organisms was performed.Non-nitrofurazone contacting shrimp samples were provided by three aquaculture bases.Four organism sections of shrimps including shrimp shell,heads,feet,and muscle were analyzed.The results showed that the detection rate of semicarbazide in the shrimp shell,heads and feet was 100%,and was 64.0%in muscle respectively.It was indicated that the source of semicarbazide in shrimps was complex,not only nitrofurazone metabolite but also exogenous sources,such as the pollution in aquaculture water,the process of predation and hypochlorite disinfectant.The results should contribute to a better understanding of the high semicarbazide positive problem for shrimp muscle tissue.In summary,an efficient and reliable method for the detection of nitrofuran residues in Deqing's farmed shrimps was established.It assures the development of local industry and market supervision,and further contributes to foundation of detection technology.In the future,further studies need to be done by comparing the semicarbazide sources of nitrofurazone and non-nitrofurazone and finally,precise and suitable criteria of shrimp's semicarbazide limitation can be established.