Novel, Selective Calix[6]Arene-Polyethylene Glycol (C6A-PEG) Stationary Phase for Capillary Gas Chromatography (GC)

A novel calix[6] arene polymer stationary phase (C6A-PEG) is reported that combines the pi-electron-rich cavity of calix[6] arene (C6A) with polyethylene glycol (PEG) units for gas chromatography (GC). Thermogravimetric analysis revealed a 5% weight loss of C6A-PEG at 318 degrees C, and its static-coated capillary column showed high efficiency of 2924 plates/m (k = 3.48) determined by 1-octanol at 120 degrees C. As a result, the moderate polar C6A-PEG column showed clearly advantageous performance for the Grob reagent and a mixture of 25 analytes with high selectivity for hydrogen-bonded acids. Also, it exhibited high resolving performance for various isomer mixtures, in particular high-resolution performance (R > 2.2) for the challenging toluidine and dimethylaniline systems with distinct advantages compared to the C6A and PEG columns (R < 1.5 for some pairs). This work demonstrates the potential of calixarene-based polymers as novel stationary phases for gas chromatographic analysis.