Development Of Fluorescence Immunoassay With Upconversion Nanoparticles Labeled Magnetic Separation For Detection Of Salbutamol

Salbutamol(SAL)belongs to β2-agonist and is a substitute substance for clenbuterol,which is of great harm to human health.Although it has been banned,there are still some criminals who use it illegally due to their interests,thus causing food safety problems.In this paper,salbutamol was used as the detection target,and the green fluorescent NaYF4:Yb,Er converted nanomaterial was used as the fluorescent signal marker.Meanwhile,a rapid fluorescence immunoassay method for the detection of albuterol in animal-derived food was established in combination with the immunoassay method.Oil soluble up-conversion nanomaterials(OA-UCNPs)were synthesized by thermal decomposition(excitation wavelength 980 nm,emission wavelength 550 nm),polyacrylic acid(PAA)is modified to the OA-UCNPs surface by ligand exchange to convert it into water-soluble carboxyl-rich surface converted nanomaterials(PAA-UCNPs).It was conjugated with antibody to prepare signal probe.The carboxylated magnetic polystyrene microspheres(MPMs)were primordially coupled with SAL to prepare induction probes.Optimizing a number of conditions later,eventually measuring the amount of adding signal probe and sensing probe,they were 50 μL and 40 μL separately,the amount of sample was 50 μL,the detection time was 30 minutes,The detection line of this method was confirmed to be 2×10-4 μg L-1,the linear range was 0.001～50 μg L-1(R2=0.9922).After the samples of beef,mutton,pork and chicken are extracted,the extracts can be diluted and then tested.The quantitative limit of SAL in the samples is 0.05 g kg-1,and the recovery rate of the samples is between 83.53%and 107.94%.HPLC/MS method and commercial ELISA method were used to compare and verify the accuracy of this method.HPLC/MS method showed that the recovery rate of the sample was between 91.79%and 109.38%,and the recovery rate of the sample was between 77.49%and 114.92%by commercial ELISA kit.The test results of the method established in this paper were consistent with those of the instrument test method and the commercial kit method,indicating that this method had good accuracy.To sum up,the up-conversion labeled magnetic separation fluorescence immunoassay method established in this study is simple to operate,rapid to detect and highly sensitive.It is suitable for the rapid detection of β2-agonist in food of animal origin,and provides a useful detection tool for monitoring the illegal use of illegal veterinary drugs.