Characterization of the efficiency of microbore liquid chromatography columns by van Deemter and kinetic plot analysis

Abstract

The efficiency of miniaturized liquid chromatography columns with inner diameters between 200 and 300 μm has been investigated using a dedicated micro-liquid chromatography system. Fully porous, core-shell and monolithic commercially available stationary phases were compared applying van Deemter and kinetic plot analysis. The sub-2 μm fully porous as well as the 2.7 μm core-shell particle packed columns showed superior efficiency and similar values for the minimum reduced plate heights (2.56-2.69) before correction for extra-column contribution compared to normal-bore columns. Moreover, the influence of extra-column contribution was investigated to demonstrate the difference between apparent and intrinsic efficiency by replacing the column by a zero dead volume union to determine the band spreading caused by the system. It was demonstrated that 72% of the intrinsic efficiency could be reached. The results of the kinetic plot analysis indicate the superior performance of the sub-2 μm fully porous particle packed column for ultra-fast liquid chromatography.

Methods to determine the kinetic performance limit of contemporary chromatographic techniques

“…Although the majority of the publications regarding the kinetic plot method relate to RPLC in normal of narrow bore packed bed columns, it has also been applied for chiral analysis [32–35], size‐exclusion chromatography (SEC) [14,36–39], comparison of packed columns with monolithic columns, and optimization of the latter's synthesis [16,40–46], to study the advantages of high temperature LC [47–48], performance of HILIC versus RPLC [49–50], microbore [51–52], open tubular [45,53,54], and pillar array columns [55–59], or to study the effect of the analyte on the kinetic performance limits [60–61]. In these cases, no significant changes to the method are required to establish the kinetic performance limits.…”

Performance in (Ultra‐)high‐performance liquid chromatography—How to qualify and optimize instruments in practice

“…This enables the comparison of 3 μm fully porous particles with 5 μm superficially porous particles [29], which is tested in this work, and further comparisons of varying particle sizes [26,30]. Comparability between different stationary phases is achieved by utilizing a constant retention factor (k-value) [31,32].…”

Separation efficiency kinetics of capillary flow micro-pillar array columns for liquid chromatography

“…Thus far, all published work on micro-pillar array columns was related to columns and applications situated in the nano-LC flow rate regime [10][11][12][13]. Whereas the huge interest in proteomics gave an enormous boost to the activity in the nano-LC application area [14][15][16][17], publications on the capillary LC (and micro-LC) flow rate range are relatively scarce, despite the potential advantages that are expected by going to larger flow rates (increased robustness, increased detection signal) [18][19][20][21][22].…”