Application of CPF Technique to the Optimization of Conditions for Separation of 6 Isomers of Dinitrotoluene by MECC

Separation of 6 isomers of dinitrotoluene (DNT) was studied by the capillary partial filling (CPF) micellar electrokinetic capillary column chromatography (MECC) and conditions for the separation were optimized by using the method of orthogonal experimental design.A buffer mixture containing solutions of 30 mmol·L-1 SDS,10 mmol·L-1 Brij 35,6 mmol·L-1 β-CD,20 mmol·L-1 borax and 5 mmol·L-1 NaH2PO4 was used in the separation,and time of sample introduction of 6 s,as well as the separation voltage of 18 kV were adopted for the separation.Under the optimized conditions,stable and flat base line,low background,highly sensitive detection and high separation efficiency were achieved.