Study On The Retention Time Prediction And The Separation Optimization For Sulfonamides Residue In The Two Dimensional Liquid Chromatography

The items in food residue detection are becoming more and more,and limit of detection is also getting lower and lower,the traditional one dimensional chromatography analysis can not meet the needs of the residue analysis.Two dimensional liquid chromatography has a larger peak capacity and higher resolution,and can simplify the sample pretreatment.If the retention time of the sample components under any gradient elution conditions can be easily calculated,not only can reduce the number of pre experiment,but also can effectively screen out the optimal gradient elution process.In this paper,a model for predicting the retention time under gradient elution in two dimensional liquid chromatography is constructed based on the theory of plate,the fast screening of the relative optimal gradient elution conditions for a variety of veterinary drug residues in two dimensional liquid chromatography is achieved by combining simple optimization model.First,the establishment of the retention model is introduced.Among six retention models,the model with the best goodness and the minimum relative error and relative standard deviation is selected to fit the relationship between the capacity factor and temperature of the 16 components in HILIC column and Sunfire C18 column,respectively.In order to validate the prediction model,the gradient elution time in one dimensional liquid chromatography is calculated.In HILIC column,the average relative error of the prediction results was 0.08%.In Sunfire C18 column,the average value of relative error was-0.47%.Using the prediction model,the retention time of analytes were predicted under gradient conditions in two dimensional LC.The average relative error of the prediction results for all the gradient conditions was-0.01%,the relative error was 1.60%,the relative errors within ±3% counted 88.02%.Finally,the retention time prediction model and the simple optimization model were used to rapidly optimize the gradient elution conditions of 16 kinds of components in the two dimensional LC.The most of the 16 kinds of veterinary drug residues in the final determination of the relative optimal conditions have been well separated.