| Flow-through pore characteristics of monolithic silicas and their impact on column performance in high-performance liquid chromatography. | |
| | |
MedLine Citation:
|
PMID: 19233368 Owner: NLM Status: MEDLINE |
Abstract/OtherAbstract:
|
In order to elucidate the role of the flow-through characteristics with regard to the column performance in high-performance liquid chromatography (HPLC) native and n-octadecyl bonded monolithic silica rods and columns, respectively of 100 mm length and 4.6 mm ID with mesopores in the range between 10 and 25 nm and macropores in the range between 0.7 and 6.0 microm were examined by mercury intrusion/extrusion, scanning electron microscopy, image analysis and permeability. The obtained data of the flow-through pore sizes and porosity values as well as surface-to-volume ratio of the stationary phase skeleton enabled to predict their influence to the chromatographic separation efficiency. Our data demonstrate that mercury porosimetry is a reliable technique to obtain all the characteristic parameters of the flow-through pores of silica monoliths. An important result of our examination was that the surface-to-volume ratio of monolithic silica skeletons had more significant impact to the separation process, rather than the average flow-through pore sizes. We could also show the essential differences between the particulate and monolithic stationary phases based on theoretical computation. The results, obtained from other characterization methods also indicated the structural complexity of monolithic silica samples. Permeability of columns is a generally applicable parameter to characterize all chromatographic phases no matter the chemistry or format. The correlation coefficient obtained for mercury intrusion and permeability of water was 0.998, though our investigation revealed that the surface modification is more likely influencing the obtained results. Further, the assumption of the cylindrical morphology of flow-through pores is not relevant to the investigated monolithic silica columns. These results on the morphology of the flow-through pores and of the skeletons were confirmed by the image analysis as well. Our main finding is that the flow-through pore sizes are not relevant for the estimation of the chromatographic separation efficiency of monolithic silica columns. |
| | |
Authors:
|
R Skudas; B A Grimes; M Thommes; K K Unger |
Publication Detail:
|
Type: Journal Article Date: 2009-01-29 |
Journal Detail:
|
Title: Journal of chromatography. A Volume: 1216 ISSN: 1873-3778 ISO Abbreviation: J Chromatogr A Publication Date: 2009 Mar |
Date Detail:
|
Created Date: 2009-03-09 Completed Date: 2009-05-12 Revised Date: - |
Medline Journal Info:
|
Nlm Unique ID: 9318488 Medline TA: J Chromatogr A Country: Netherlands |
Other Details:
|
Languages: eng Pagination: 2625-36 Citation Subset: IM |
Affiliation:
|
Institut für Anorganische Chemie und Analytische Chemie, Johannes Gutenberg University, Duesbergweg 10-14, D-55099 Mainz, Germany. |
Export Citation:
|
APA/MLA Format Download EndNote Download BibTex |
| MeSH Terms | |
Descriptor/Qualifier:
|
Chromatography, High Pressure Liquid
/
methods* Microscopy, Electron, Scanning Porosity Silicon Dioxide / chemistry* |
| Chemical | |
Reg. No./Substance:
|
7631-86-9/Silicon Dioxide |
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
Previous Document: Application of capillary affinity electrophoresis and density functional theory to the investigation...
Next Document: Multi-residue off-flavour profiling in wine using stir bar sorptive extraction-thermal desorption-ga...