Monolithic bed structure for capillary liquid chromatography

Aggarwal, Pankaj; Tolley, H. Dennis; Lee, Milton L.

doi:10.1016/j.chroma.2011.10.083

Cited by 77 publications

(57 citation statements)

References 117 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The bed structures of monolithic capillary columns, such as the pore size and distribution, determine the separation efficiency [52]. Undesirable pore size and nonuniform structure may limit the separation performance.…”

Section: Discussionmentioning

confidence: 99%

“…Monolith-based cLC for protein and peptide analysis Monolithic capillary columns have been widely applied for protein and peptide separation by cLC, with the advantages of relatively facile preparation, fast mass transfer, low backpressure, and high permeability. Polymer monoliths show better performance for protein separation than silica monoliths because of their biocompatibility and large domain size morphology [51,52]. However, the lack of mesopores and the presence of an inhomogeneous structure lead to a low surface area, which is unfavorable for high-efficiency separation, especially for peptides with relatively low molecular weight.…”

Section: Organic-silica Hybrid Monolithsmentioning

confidence: 99%

“…However, the lack of mesopores and the presence of an inhomogeneous structure lead to a low surface area, which is unfavorable for high-efficiency separation, especially for peptides with relatively low molecular weight. Silica monoliths have a bimodal pore size distribution with a significant fraction of mesopores [52], resulting in a high surface area, which ensures good separation performance. Currently, silica monoliths are successfully applied for peptide separation with high efficiency, especially in reversed-phase liquid chromatography (RPLC) mode.…”

Section: Organic-silica Hybrid Monolithsmentioning

confidence: 99%

See 2 more Smart Citations

Recent advances in monolithic columns for protein and peptide separation by capillary liquid chromatography

Liang

Zhang

2012

Anal Bioanal Chem

View full text Add to dashboard Cite

Capillary liquid chromatography (cLC) has great potential for protein and peptide separation, with advantages of high efficiency, high resolution, low sample consumption, and high sensitivity when coupled with mass spectrometry. In recent years, monoliths have been widely used as the stationary phases for capillary columns, owing to easy preparation, high permeability, fast mass transfer, and low backpressure. This review summarizes recent advances (2007)(2008)(2009)(2010)(2011)(2012) in monolithic columns for protein and peptide separation by cLC. After a brief introduction on the preparation of monolithic capillary columns, the emphasis of this review is focused on the recent application of such columns for protein and peptide separation by cLC. Furthermore, the challenges and potential hot points of monolithic capillary columns in the future are discussed.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Organic-silica Hybrid Monolithsmentioning

confidence: 99%

Section: Organic-silica Hybrid Monolithsmentioning

confidence: 99%

See 1 more Smart Citation

Recent advances in monolithic columns for protein and peptide separation by capillary liquid chromatography

Liang

Zhang

2012

Anal Bioanal Chem

View full text Add to dashboard Cite

show abstract

“…Use of smaller particles relative to the microchannel size also improves bed structure homogeneity as well as reduce 'wall effects' (Aggarwal et al, 2012), which lead to the fluid preferentially channelling along the walls rather than passing through the bed. However, as pressure drop and, therefore, pumping power tends to increase as the particle size drops (Unger et al, 2008, Dautzenberg and Mukherjee, 2001, DeStefano et al, 2008, a trade-off in the particle-tomicrochannel size must be accepted.…”

Section: Introductionmentioning

confidence: 99%

“…Spherical particles are commonly used to form µPBs as they tend to ease the formation of more homogeneous bed structures that are known to give the best heat and mass transfer performance (Aggarwal et al, 2012). Use of smaller particles relative to the microchannel size also improves bed structure homogeneity as well as reduce 'wall effects' (Aggarwal et al, 2012), which lead to the fluid preferentially channelling along the walls rather than passing through the bed.…”

Section: Introductionmentioning

confidence: 99%

A new method for reconstruction of the structure of micro-packed beds of spherical particles from desktop X-ray microtomography images. Part A. Initial structure generation and porosity determination

Kashani

Živković

Elekaei

et al. 2016

Chemical Engineering Science

View full text Add to dashboard Cite

Citation: NAVVAB KASHANI, M. ...et al., 2016. A new method for reconstruction of the structure of micro-packed beds of spherical particles from desktop X-ray microtomography images. Part A. Initial structure generation and porosity determination. Chemical Engineering Science, 146, Additional Information:• This paper was accepted for publication in the journal Chemical En- AbstractMicro-packed beds (µPBs) are seeing increasing use in the process intensification context (e.g. micro-reactors), in separation and purification, particularly in the pharmaceutical and bio-products sectors, and in analytical chemistry. The structure of the stationary phase and of the void space it defines in such columns is of interest because it strongly influences performance. However, instrumental limitations -in particular the limited resolution of various imaging techniques relative to the particle and void space dimensions -have impeded experimental study of the structure of µPBs. We report here a new method that obviates this issue when the µPBs are composed of particles that may be approximated by monodisperse spheres. It achieves this by identifying in successive cross-sectional images of the bed the approximate centre and diameter of the particle cross-sections, replacing them with circles, and then assembling them to form the particles by identifying correlations between the successive images. Two important novel aspects of the method proposed here are it does not require specification of a threshold for binarizing the images, and it preserves the underlying spherical geometry of the packing. The new method is demonstrated through its application to a packing of a near-monodispersed 30.5 µm particles of high sphericity within a 200 µm square cross-section column imaged using a machine capable of 2.28 µm resolution. The porosity obtained was, within statistical uncertainty, the same as that determined via a direct method whilst use of a commonly used automatic thresholding technique yielded a result that was nearly 10% adrift, well beyond the experimental uncertainty. Extension of the method to packings of spherical particles that are less monodisperse or of different regular shapes (e.g. ellipsoids) is also discussed.

show abstract

Integrated electrokinetically driven microfluidic devices with pH‐mediated solid‐phase extraction coupled to microchip electrophoresis for preterm birth biomarkers

2017

View full text Add to dashboard Cite

Integration in microfluidics is important for achieving automation. Sample preconcentration integrated with separation in a microfluidic setup can have a substantial impact on rapid analysis of low-abundance disease biomarkers. Here, we have developed a microfluidic device that uses pH-mediated solid phase extraction (SPE) for the enrichment and elution of preterm birth (PTB) biomarkers. Furthermore, this SPE module was integrated with microchip electrophoresis for combined enrichment and separation of multiple analytes, including a PTB peptide biomarker (P1). A reversed-phase octyl methacrylate monolith was polymerized as the SPE medium in polyethylene glycol diacrylate modified cyclic olefin copolymer microfluidic channels. Eluent for pH-mediated SPE of PTB biomarkers on the monolith was optimized using different pH values and ionic concentrations. Nearly 50-fold enrichment was observed in single channel SPE devices for a low nanomolar solution of P1, with great elution time reproducibility (<7% RSD). The monolith binding capacity was determined to be 400 pg (0.2 pmol). A mixture of a model peptide (FA) and a PTB biomarker (P1) was extracted, eluted, injected, and then separated by microchip electrophoresis in our integrated device with ~15-fold enrichment. This device shows important progress towards an integrated electrokinetically operated platform for preconcentration and separation of biomarkers.

show abstract

Monolithic bed structure for capillary liquid chromatography

Cited by 77 publications

References 117 publications

Recent advances in monolithic columns for protein and peptide separation by capillary liquid chromatography

Recent advances in monolithic columns for protein and peptide separation by capillary liquid chromatography

A new method for reconstruction of the structure of micro-packed beds of spherical particles from desktop X-ray microtomography images. Part A. Initial structure generation and porosity determination

Integrated electrokinetically driven microfluidic devices with pH‐mediated solid‐phase extraction coupled to microchip electrophoresis for preterm birth biomarkers

Contact Info

Product

Resources

About