Novel stationary phase for complexation gas chromatography originating from ionic liquid and metallomesogen

A metallomesogen of a polycatenar oxazoline copper(II) complex, [Cu(S-C12)2], that exhibited a columnar mesophase with a helical organization was prepared and employed as the stationary phase for the GC separation with polycyclic aromatic hydrocarbons (PAHs) as model compounds. For introducing the mesogen into the capillary column, an ionic liquid (BeMIM-TfO) was used as the vehicle. The results of thermal analyses and UV–vis spectroscopy indicated that some beneficial interactions occurred between the metallomesogen and the ionic liquid. Various parameters affecting the separation efficiency were studied. Different ratios of BeMIM-TfO and Cu(S-C12)2 (1:0, 1:1, 1:2 and 1:3 (w/w)) were tested for the separation of the PAHs. As the amount of Cu(S-C12)2 was increased, complete separation could be achieved. The stationary phase with the ratio of 1:1 provided the most satisfactory result having average theoretical plate number of 5.2 × 103 plates/m. With an optimized temperature program, 11 PAH mixtures were completely separated within 27 min. The interaction between PAH and these fascinating and interesting stationary phases was discussed.