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Uva-DARE (Digital Academic Repository) UvA-DARE (Digital Academic Repository) Design and fabrication through additive manufacturing of devices for multidimensional LC based on computational insights Adamopoulou, T. Publication date 2020 Document Version Other version License Other Link to publication Citation for published version (APA): Adamopoulou, T. (2020). Design and fabrication through additive manufacturing of devices for multidimensional LC based on computational insights. General rights It is not permitted to download or to forward/distribute the text or part of it without the consent of the author(s) and/or copyright holder(s), other than for strictly personal, individual use, unless the work is under an open content license (like Creative Commons). Disclaimer/Complaints regulations If you believe that digital publication of certain material infringes any of your rights or (privacy) interests, please let the Library know, stating your reasons. In case of a legitimate complaint, the Library will make the material inaccessible and/or remove it from the website. Please Ask the Library: https://uba.uva.nl/en/contact, or a letter to: Library of the University of Amsterdam, Secretariat, Singel 425, 1012 WP Amsterdam, The Netherlands. You will be contacted as soon as possible. UvA-DARE is a service provided by the library of the University of Amsterdam (https://dare.uva.nl) Download date:25 Sep 2021 Symbols and Abbreviations PFHDA 1H,1H,6H,6H-Perfluoro-1,6-hexyl diacrylate 1 D first dimension 1D one-dimensional 2 D second dimension 2DLC two-dimensional LC 2D-PAGE 2D – poly(acryl amide) gel electrophoresis 2DTLC two-dimensional thin layer chromatography 2PP two-photon polymerization 3 D third dimension 3DLC three-dimensional LC ABS acrylonitrile− butadiene−styrene CAD computer aided design CE capillary electrophoresis CFD computational fluid dynamics CGE capillary gel electrophoresis COC cyclic olefin copolymer COSMIC channel of separation with many individual controls DIGE difference gel electrophoresis DLP digital-light-processing EPDM ethylene propylene diene monomer FD flow-distributor FDM finite difference method FEM finite element method FFKM perfluoroelastomer FVM finite volume method HPLC high performance liquid chromatography HPTLC high-performance thin-layer chromatography - 135 - Symbols and abbreviations IEF iso-electric focusing IMER immobilized enzyme reactor LC Liquid-Chromatography LC×LC two-dimensional liquid chromatography LIF laser-induced fluorescence MALDI-MS matrix-assisted laser-desorption/ionization mass spectrometry OPLC overpressured layer chromatography PDE partial differential equations PDMS poly(dimethylsiloxane) PEG-DA polyethylene glycol diacrylate RPLC Reverse-phase Liquid Chromatography SDS-PAGE Sodium Dodecyl Sulphate-Polyacrylamide Gel Electrophoresis SIMPLE Semi-Implicit Method for Pressure Linked Equations SLIT Simple Liquid Transfer SLM Selective laser melting STAMP Separation Technology for A Million Peaks TDMA tri-diagonal matrix algorithm TLC thin-layer chromatography t LC temporal liquid chromatography t t LC× LC temporal two-dimensional liquid chromatography t t t LC× LC× LC temporal three-dimensional liquid chromatography TWIST TWo-dimensional Insertable Separation Tool UHPLC ultra high performance liquid chromatography UNC unified coarse thread UV ultraviolet x LC spatial liquid chromatography xLC×tLC two-dimensional liquid chromatography with spatial first- dimension and temporal as a second x x LC× LC spatial two-dimensional liquid chromatography xLC×xLC×tLC three-dimensional liquid chromatography with spatial the first two dimensions and temporal as a third x x x LC× LC× LC spatial three-dimensional liquid chromatography - 136 - Symbols and abbreviations n peak capacity N number of theoretical plates L length H plate height spatial variance in length units tR retention time of the analyte peak variance in time units 3Dn peak capacity of 3D-LC 1n peak capacity of the first dimension 2n peak capacity of the second dimension 3n peak capacity of the third dimension 3D tω analysis time of 3D-LC 1 tω analysis time of the first dimension 2 tω analysis time of the second dimension 3 tω analysis time of the third dimension zf development distance t development time u velocity (x-direction) ρ density body force τ stress force p pressure µ(0) zeroth moment µ’(1) first moment µ’(2) second moment c(x) concentration x spatial in the direction of the development σ2 variance Kfdb permeability value of the flow-distributor barriers 2 K2 D separation zone 3 K3 D Cube permeability 3 K3DFD permeability of the imposed porous zone in the top part of the D flow distributor φ mass fraction V cell volume w width - 137 - Symbols and abbreviations D diffusion coefficient εe external porosity K permeability dp particle diameter niso peak capacity (isocratic mode) Rs resolution between two consecutive peaks kw retention factor of the most-retained compound ka retention factor of the least-retained compound ngrd peak capacity (gradient mode) tG gradient time σpeak peak dispersion under gradient conditions tm dead time ke retention factor at the moment of the elution S slope of the line that describes retention (ln k) as a function of the mobile-phase composition Δφ range in composition covered by the gradient z distance along the separation medium 4σ width of the spot 2 σi initial variance of the spot γ tortuosity D diffusion coefficient of the analyte t development time v velocity (y-direction) w velocity (z-direction) p pressure mean value of velocity u' fluctuating value of velocity external force Reynolds stress U quantity F flux Q source A surface - 138 - Summary One-dimensional column-based liquid-chromatography systems do not provide the necessary separation power for the analysis of complex samples. Column-based two- dimensional systems offer higher selectivity and peak capacity. However, they suffer from longer analysis times. Spatial two-dimensional liquid chromatography (xLCxLC) may prove to be an efficient solution, as the peak capacity of the system is ideally the product of the peak capacities of the two dimensions, while the analysis time remains relatively short due to separations performed in parallel. Adding a third dimension can potentially yield peak capacities in the order of one million, even at modest pressures. The main aspects we need to investigate to create devices for this purpose include flow distribution to enhance uniformity, analyte transfer between dimensions, band broadening, and confinement of the flow in each dimension. The aim of this thesis is to investigate various designs and arrangements for spatial two- and three-dimensional liquid chromatography, considering band-broadening, analyte-transfer and flow-confinement aspects. Synergies between computational and experimental work were exploited. Computational-fluid-dynamics simulations were conducted to provide insights, which would have been extremely time-consuming or difficult and, in some cases, even impossible to obtain experimentally. For the fabrication of the devices 3D-printing was employed. Different 3D-printing methods were used, with stereolithography playing a dominant role. In Chapter 1 a refresher of planar chromatography is provided, as the suggested two- dimensional devices in this thesis are a continuation of such methods. Additionally, an introduction to computational fluid dynamics is included. - 139 - Summary In Chapter 2 band-broadening and analyte-transfer aspects of devices for xLCxLC were investigated. First, effects of the type of geometry of the second dimension, viz. flat bed or channels, as well as the presence or absence of stationary-phase material in the first dimension were examined computationally. It was observed that a second dimension in the form of a flat bed performed best in terms of band-broadening. The stationary-phase material in the first-dimension (1D) channel significantly affected both band-broadening and analyte transfer. In the most-favourable case porous zones were present in both the 1D and 2D regions. The devices were fabricated using 3D-printing, more specifically stereolithography. The devices were then tested in terms of flow and pressure. In Chapter 3 the importance of flow confinement for xLCxLC devices is highlighted with the aid of CFD simulations. A modular active-flow-confinement mechanism is introduced, the so-called TWIST (Two-dimensional Insertable Separation Tool). The valve mechanism is based on an assembly of two parts, an internal and an external one. Both parts have through-holes at the same coordinates. When the through-holes of the two parts are not aligned leakage is prevented and the 1D injection – and eventually separation – can take place. Then, for the analytes separated in the 1D channel to be transferred to the second dimension and for the 2D separation to take place, the through- holes of the two parts are aligned. Stereolithography was employed for the fabrication of the device described in this chapter. The patent that covers both the TWIST device described in this chapter and the SLIT device described in Chapter 5 is appended to this chapter. In Chapter 4 aspects of flow confinement are discussed in more detail. The feasibility of a passive-flow-confinement mechanism based on porous barriers and differences in permeability between dimensions is examined for devices for spatial two- and three- dimensional liquid chromatography. The necessary permeability values are determined through computational fluid dynamics simulations. Additionally, the impact of the design and operation
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