Preparation And Chiral Separation Application Of Electrochromatographic Column Based On Acryloyl-β-cyclodextrin/Nanometer Nickel Oxide Composites

In this paper, propylene acyl-β-cyclodextrin and chemical modification of nano nickel oxide microspheres synthesized by solvent thermal method were prepared successfully.Infrared ray, thermogravimetry and scanning electron microscope were used to characterize their functional groups and morphology.The results showed modified nickel oxide microspheres were constructed by nanoplatelets with uniform thickness, the microsphere diameter was about 1μm, the morphology of the microsphere was intact, regular and uniform.Two kinds of monolithic column, propylene acyl-β-cyclodextrin/nano nickel oxide and propylene acyl-β-cyclodextrin as stationary phase, respectively, were prepared by one-step bonding method.Influence factor on the preparation of the column including the dosage of dodecanol as pore-forming agent, the dosage of azobisisobutyronitrile as initiating agent, reaction temperature and time were discussed, optimal preparation conditions of the column were obtained: 0.17 g of dodecanol, 0.0016 g of AIBN, 40 ℃ of temperature and 8 h. Stationary phase in the columns was characterized by scanning electron microscope and energy spectrum.It was found that stationary phase in the two kinds of monolithic column bonded tightly and distributed uniformly, the content of nickel oxide in the composite column was about 33%, but the morphology of the two kinds of monolithic columns was different. The column of propylene acyl-β-cyclodextrin has interpenetration structure, however, the interior of the composite monolithic column presented granulometric state, greater internal porosity, and more permeation.Under the same electrochromatographic condition, the performance of two kinds of monolithic columns was assessed and compared with thiourea and DL-valine as analytes. For the composite column, the average retention time, column efficiency and resolution of DL-valine were 5.698 min, 8.0 ×104 plates/m and 3.62, respectively.However, for propylene acyl-β-cyclodextrin column, were 6.674 min, 5.1×104 plates/m, 3.18, respectively.It can be observed that the retention time of the composite column was shorter, the column efficiency was higher, the resolution was better.The composite column was applied to separate Atenolol, Sotalol and Metoprolol enantiomers with aminopropanol structures. During the separation, p H value of buffer solution, separation voltage and temperature were optimized. Under the best electrochromatographic conditions, all the enantiomers of the three chiral drugs reached the baseline separation.