Column-in-valve designs to minimize extra-column volumes.

J Chromatogr A

Department of Chemical Engineering, Vrije Universiteit Brussel, Brussels, Belgium. Electronic address:

Published: January 2021

We report on the design and performance of in-house built column cartridges that can be directly screwed into the ports of a commercial rotor-stator valve to minimize extra-column band broadening and pressure-drop losses when pursuing ultra-fast separations such as those needed in 2D and 3D-LC separations. Two basic designs were evaluated and were compared with the results obtained with a commercial screw-in column cartridge. The system produces an extra-column band broadening as low as 0.05 to 0.1 μL for the employed UV-detector set-up. Despite these very low values, the obtained separation efficiency of the in-house fabricated cartridge columns was very low, corresponding to a reduced minimal plate height around h=7 at the very best, which, for the 1.7 μm particle and 26.4 mm long columns corresponds to a number of theoretical plates of N=2200 under isocratic conditions. A similar poor performance was obtained with a commercial column cartridge with similar dimensions using the same set-up. One possible explanation of the observed performance could be found in the inner diameter of the column cartridges (i.d. =0.75 mm and 1 mm) which, for the employed sub 2-μm particles, falls into a region of column diameters that, according to literature models, is most likely to suffer from inherent packing problems.

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.chroma.2020.461779DOI Listing

Publication Analysis

Top Keywords

minimize extra-column
8
column cartridges
8
extra-column band
8
band broadening
8
column cartridge
8
column
5
column-in-valve designs
4
designs minimize
4
extra-column volumes
4
volumes report
4

Similar Publications

Recently, the focus in chromatography model development has expanded to include the modeling of extra column volume (ECV), particularly in small- and lab-scale systems where ECV can constitute a significant portion of the total volume. Typically, ECV is modeled with 1D approaches, for example with combinations of dispersed plug flow reactors (DPFRs) and continuously stirred tank reactors (CSTRs). However, radial inhomogeneities in the ECV concentration profile necessitate higher-dimensional models for more accurate predictions.

View Article and Find Full Text PDF

This study introduces a feasible approach for utilizing a conventional High-Performance Liquid Chromatography (HPLC) instrument at the capillary scale (1 - 10 µL/min). The development of an active flow splitter and an adapted UV-visible (UV-vis) detection cell are described. The system employs an Arduino Uno board to monitor a flow sensor and control a stepper motor that automates a split valve to achieve capillary-scale flow rates from a conventional pump.

View Article and Find Full Text PDF

With the introduction of ultrahigh efficiency columns and fast separations, the need to eliminate peak deformation contributed by the instrument must be effectively solved. Herein, we develop a robust framework to automate deconvolution and minimize its artifacts, such as negative dips, wild noise oscillations, and ringing, by combining regularized deconvolution and Perona-Malik (PM) anisotropic diffusion methods. A asymmetric generalized normal (AGN) function is proposed to model the instrumental response for the first time.

View Article and Find Full Text PDF

Towards a simple on-line coupling of ion exchange chromatography and native mass spectrometry for the detailed characterization of monoclonal antibodies.

J Chromatogr A

October 2021

Institute of Pharmaceutical Sciences of Western Switzerland (ISPSO), University of Geneva, CMU-Rue Michel Servet 1, 1211 Geneva 4, Switzerland; School of Pharmaceutical Sciences, University of Geneva, CMU-Rue Michel Servet 1, 1211 Geneva 4, Switzerland. Electronic address:

This work describes the direct hyphenation of cation exchange chromatography (CEX) with a compact, easy-to-use benchtop Time of Flight mass spectrometer (ToF/MS) for the analytical characterization of monoclonal antibodies (mAbs). For this purpose, a wide range of commercial mAb products (including expired samples and mAb biosimilars) were selected to draw reliable conclusions. From a chromatographic point of view, various buffers and column dimensions were tested.

View Article and Find Full Text PDF

Column-in-valve designs to minimize extra-column volumes.

J Chromatogr A

January 2021

Department of Chemical Engineering, Vrije Universiteit Brussel, Brussels, Belgium. Electronic address:

We report on the design and performance of in-house built column cartridges that can be directly screwed into the ports of a commercial rotor-stator valve to minimize extra-column band broadening and pressure-drop losses when pursuing ultra-fast separations such as those needed in 2D and 3D-LC separations. Two basic designs were evaluated and were compared with the results obtained with a commercial screw-in column cartridge. The system produces an extra-column band broadening as low as 0.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!