Application of polymeric high‐internal‐phase‐emulsion‐coated stationary‐phase columns in open‐tubular capillary electrochromatography

Abstract

The application of polymeric high-internal-phase emulsion (polyHIPE) capillary coatings for open-tubular analytical separation columns was demonstrated in this study for the first time. Multiple polystyrene-co-divinylbenzene polyHIPE layers with an average total depth of 1.73 mm were coated onto internal capillary surfaces to create open-tubular columns (20 cm coating and 32.5 cm effective length). With these columns for open-tubular capillary electrochromatography, ethylbenzene and pentylbenzene were separated. Although the overall separation capacity of the produced columns was low, the polyHIPE coatings improved the analyte peak shape, decreased the total run time, and improved the peak symmetries relative to comparable unmodified open-tubular columns. In addition, the use of these novel polyHIPE columns led to the use of 30% less organic modifier. These columns have the potential to improve the shelf life of open-tubular columns typically used in capillary electrochromatography. V C 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 44237.

Recent developments in open tubular capillary electrochromatography from 2016 to 2017

“…Scanning electron microscopy (SEM) has become an indispensable characterisation method for a visual confirmation of the surface morphology of coated surfaces. SEM images of successfully coated surfaces were described to show rough surfaces , hilly or bumpy surfaces , with distinct shapes of the embedded material , good layer density and homogeneity or uniformity , and more importantly significant layer thickness as opposed to the smooth surfaces seen in bare silica surfaces. Some SEM scans were performed on flat silica surfaces for detailed characterisation because of the inherent difficulty in successfully imaging wall coatings for a capillary format.…”

“…These emulsions, with an internal droplet phase (aqueous) greater than 74% of the total emulsion volume , usually form monoliths. Choudhury and co‐workers coated multiple polystyrene‐co‐divinylbenzene polyHIPE layers onto 100 μm id x 20 cm long column . After three sequential coatings of thin films, a lace pore structure was observed by scanning electron microscopy (SEM), and the optimised coating regimen produced baseline separation of two alkylbenzenes (resolution, Rs = 2.80).…”

“…Other notable example was the derivatisation with a mercaptosilane (3‐mercaptopropyl)trimethoxysilane (MPTMS) to generate a thiol‐functionalised wall to bind GNPs in a multilayering process . In another report, 3‐(trimethoxysilyl) propyl methacrylate was used as silanisation agent to provide methacrylate groups to polymerise with the polystyrene‐co‐divinylbenzene (PS‐co‐DVB) polyHIPE emulsion . Glycidoxypropyltrimethoxysilane (GLYMO) was also used to functionalise the wall with epoxy groups to form an imine link with amino groups of the COF‐LZU1 .…”

Graphene Oxide Nanoparticles and Their Influence on Chromatographic Separation Using Polymeric High Internal Phase Emulsions

“…PolyHIPEs have been successfully applied in areas such as electrochemistry [5], tissue engineering [6,7] and solid-phase extraction [8,9]. PolyHIPEs have been developed as stationary phase materials for standard-bore liquid chromatography applications, as shown in particular in [10][11][12][13]. As polyHIPEs are macroporous materials (pores from 10 to 100 µm) they are ideal for biological separations and have been demonstrated previously in the literature [10,11,13].…”

“…As polyHIPEs are macroporous materials (pores from 10 to 100 µm) they are ideal for biological separations and have been demonstrated previously in the literature [10,11,13]. However, fewer instances of small molecule separation using high performance liquid chromatography (HPLC) methods have been utilised [12].…”