Chromatographic selectivity of graphene capillary column pretreated with bio-inspired polydopamine polymer

Abstract

This work reports the first example of employing bio-inspired polydopamine (PDA) in capillary column fabrication of a graphene stationary phase (denoted as G-PDA@capillary) for gas chromatographic (GC) separations. The as-fabricated G-PDA@capillary column achieved improved column efficiency of 3400 plates per m and separation performance in contrast to the graphene column without PDA (G@capillary). In particular, it exhibited high selectivity and resolving ability for alkane isomers, alcohol isomers, substituted benzenes with diverse groups and many other types of analytes. Additionally, the G-PDA@capillary column showed good repeatability with RSD values less than 0.02% for run-to-run, 0.16% for day-to-day and 5.0% for column-to-column, respectively, and thermal stability up to 300 °C. This work demonstrates the feasibility of the proposed strategy by integrating graphene sheets with PDA coating, which is efficient in addressing the current problem with graphene sheets and exploring its full potential in GC separations.