Performance of permethyl pillar[5]arene stationary phase for high-resolution gas chromatography

This work presents the investigation of permethyl pillar[5]arene (MP5) as stationary phase for capillary gas chromatographic (GC) separations. The MP5 capillary column fabricated by the sol-gel coating method exhibited weak polarity and high column efficiency over 4200 plates/m for n-dodecane, n-octanol and naphthalene. Particularly, the MP5 stationary phase displays unique retention for dibromoalkanes, which was found to be closely related with the linker length, and shows high resolving capability for a wide range of positional and structural isomers, including alkylbenzenes, chlorobenzenes and chloronitrobenzenes, naphthalene derivatives, phenols and anilines. Moreover, the MP5 column showed good thermal stability and repeatability and reproducibility with the relative standard deviation in the range of 0.02-0.04% for intra-day, 0.32-0.46% for inter-day and 1.5-3.4% for between-column, respectively. This work demonstrates an promising future of pillar[n]arenes as a new type of stationary phase in chromatographic separations.