Study Of The Electrochemical Rapid Determination Of Salbutamol In Feeds

This study aimed to develop a rapid method to detect the salbutamol in large quantities on the basis of electrochemical,molecular imprinting and other special compound modification technology was complementary.Evaluated the characterization and adsorption performance of molecular imprintings(MIPs)、 molecularly imprinted membrane(MIM),the adsorption effects of salbutamol molecularly imprinting modified electrode.According to the evaluation results to determine the merits of the different modificated methods,to provide theoretical support for further application of molecular imprinting technology in the actual detection.At first,this paper adopted the computer simulation method to select the optimum monomer and optimal proportion.We choosed the usually used Hyperchem8.0 software to find the lowest energy conformation of different monomer,got their charge distribution.Then simulate the complexes combination of template and different ratio of monomer,got their binding energy.Selected the optimum monomer and optimal proportion by the simulation results,synthesised traditional MIPs,NIPs and new type of core-shell MIPs,NIPs.The second step was analysis the characterization of MIPs,NIPs by ultraviolet absorption spectra(UV spectra),Fourier infrared spectra(FTIR)and Raman spectroscopy(Raman spectra),Scanning electron microscopy(SEM)methods.According to the experimental results,SAL and MA had specific binding to form hydrogen bond complexes.After elution,there arised some holes on MIPs which very matched to SAL.They could specific recognition and binding specificity with SAL in the test liquid,and the adsorption ability of MIPs was obviously higher than that of NIPs.The adsorption capacity of MIPs was significantly higher than that of NIPs.And colloidal gold core-shell MIPS was not only had the above characteristics,its surface was more loose,have more holes compared with conventional MIPs.Thus the effective area to adsorbed target molecules was increased,so colloidal gold core-shell MIPShas better adsorption performance.The third step was for current-mode electrochemical detection.Evaluated detection performance through current mode sensor by bare electrode first.Then use the MIM,TCNQ-colloidal gold modification electrode for detection performance evaluation.Results show that the signal increase effect of these two electrodes were ideal,and repeatability was strong.The accuracy、recovery and interference index of test results was ideal.The performance of TCNQ-colloidal gold modification electrode was better.Using this electrode to test samples,Results revealed that linear range of 0.65 ~ 10 mg/L,detection limit(3 sigma)can reach 0.62 mg/L,the average recovery was 94.3%.The accuracy of this method could meet the needs of screen detection of the samples,and the cost was quite low,Detection time of one sample was less than 2 mins.The fourth step was study on conductance type electrochemical detection.Still used silk screen printing electrode,sensor changed for electrochemical sensor conductivity type.Evaluated the detection performance through the bare electrode,and then evaluated the detection performance with MIM and graphene-nanometer gold modification electrode.The results showed that solution conductivity could be greatly improved after using MIM and graphene-nanometer gold modified electrode.But,because the graphene-nanometer gold electrode has no specific identificate capability to of SAL,its sensitivity and repetition rate was therefore not ideal compared with MIM modified electrode.The linear range detection limit(3 sigma)could reach 0.03 mg/L,the average recovery was 91%.This method using portable instrumentins,suitable for field testing besides with the advantages of current mode detection method.Studies have shown that the sensitivity,repeatability,accuracy of electrochemical sensing detection method for SAL could be effectively improved by properly modified.Therefore improved electrochemical detection method can not only meet the needs of high sensitivity,high stability,repeatability and high accuracy requirements in detection work.At the same time it also had many advantages such as simple technology,instrument cabinet,short detection time,fast sample preparation,low cost advantages and so on.So this method had a good application prospect in the scene detection of a large number of salbutamol.In the four kinds of detection methods in this paper,three could satisfy the requirement of on-site detection of a large number.And the MIM modified electrode conductance sensor detection method had the most applied value.Its linear range was 0.5 to 15 mg / L,lower limit of detection was 0.03 mg / L.