General approach for certain quantitative calculations for Instance of the variance of reversible adsorption to the capillary wall in CE
Farkas, Viktor ; Rezeli, Melinda LU
; Végvári, Ákos
LU
; Kilár, Ferenc
and Hjertén, Stellan
(2009)
In Analytical Chemistry
81(1).
p.343-348
- Abstract
- Miniaturization of analytical separation methods offers several advantages, including short run times, high resolution, and high recovery of the sample constituents. To optimize these parameters, the reversible adsorption (to minimize loss in resolution), as well as the irreversible adsorption (to minimize loss of analytes) must be quantified. However, no useful equation is available for the calculation of the variance of reversible adsorption. Therefore, we have taken another approach to quantify the reversible interaction. The method is unique and important since no equation for calculation of this variance is required. Instead, two experiments are required, which are run under such conditions that the variance of a certain parameter has... (More)
- Miniaturization of analytical separation methods offers several advantages, including short run times, high resolution, and high recovery of the sample constituents. To optimize these parameters, the reversible adsorption (to minimize loss in resolution), as well as the irreversible adsorption (to minimize loss of analytes) must be quantified. However, no useful equation is available for the calculation of the variance of reversible adsorption. Therefore, we have taken another approach to quantify the reversible interaction. The method is unique and important since no equation for calculation of this variance is required. Instead, two experiments are required, which are run under such conditions that the variance of a certain parameter has the same numerical value in the two experiments (one with and without EOF), except for the variance of reversible adsorption. The approach is universal in the sense that it can be used for many different mathematical concepts and be modified to also cover certain functions other than a sum of parameters. We have also introduced a simple expression for the irreversible adsorption, which shows that the hydrophobic interaction from only two methyl groups in the coating gives rise to as much as 40-50% loss of protein, and the width of the zones in the capillary with this coating was 8-15% larger compared to the zone width in the polyacrylamide-coated capillaries. The reproducibility in migration time, peak area, and peak width in two consecutive runs in capillaries with two methyl groups in the coating was very low, but in EOF-free polyacrylamide-coated capillaries extremely high, indicating that the reversible and irreversible adsorption of proteins to this coating is negligible. The scanning detector, frequently used in free zone electrophoresis in the 1960s-1970s, gives true separation parameters and is, therefore, much preferable to the stationary detector used in most CE experiments, because this detector gives apparent separation parameters. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/1235324
- author
- Farkas, Viktor
; Rezeli, Melinda
LU
; Végvári, Ákos
LU
; Kilár, Ferenc
and Hjertén, Stellan
- organization
- publishing date
- 2009
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- electroosmotic flow, variance, EOF, plate number, coating, adsorption, microchip electrophoresis, capillary electrophoresis, mass spectrometry
- in
- Analytical Chemistry
- volume
- 81
- issue
- 1
- pages
- 343 - 348
- publisher
- The American Chemical Society (ACS)
- external identifiers
-
- pmid:19035645
- wos:000262113400049
- scopus:58149462262
- ISSN
- 1520-6882
- DOI
- 10.1021/ac8010457
- language
- English
- LU publication?
- yes
- id
- 14845b2f-1e9b-42a2-9202-6903b361e115 (old id 1235324)
- date added to LUP
- 2016-04-01 11:37:24
- date last changed
- 2023-09-01 00:47:23
@article{14845b2f-1e9b-42a2-9202-6903b361e115,
abstract = {{Miniaturization of analytical separation methods offers several advantages, including short run times, high resolution, and high recovery of the sample constituents. To optimize these parameters, the reversible adsorption (to minimize loss in resolution), as well as the irreversible adsorption (to minimize loss of analytes) must be quantified. However, no useful equation is available for the calculation of the variance of reversible adsorption. Therefore, we have taken another approach to quantify the reversible interaction. The method is unique and important since no equation for calculation of this variance is required. Instead, two experiments are required, which are run under such conditions that the variance of a certain parameter has the same numerical value in the two experiments (one with and without EOF), except for the variance of reversible adsorption. The approach is universal in the sense that it can be used for many different mathematical concepts and be modified to also cover certain functions other than a sum of parameters. We have also introduced a simple expression for the irreversible adsorption, which shows that the hydrophobic interaction from only two methyl groups in the coating gives rise to as much as 40-50% loss of protein, and the width of the zones in the capillary with this coating was 8-15% larger compared to the zone width in the polyacrylamide-coated capillaries. The reproducibility in migration time, peak area, and peak width in two consecutive runs in capillaries with two methyl groups in the coating was very low, but in EOF-free polyacrylamide-coated capillaries extremely high, indicating that the reversible and irreversible adsorption of proteins to this coating is negligible. The scanning detector, frequently used in free zone electrophoresis in the 1960s-1970s, gives true separation parameters and is, therefore, much preferable to the stationary detector used in most CE experiments, because this detector gives apparent separation parameters.}},
author = {{Farkas, Viktor and Rezeli, Melinda and Végvári, Ákos and Kilár, Ferenc and Hjertén, Stellan}},
issn = {{1520-6882}},
keywords = {{electroosmotic flow; variance; EOF; plate number; coating; adsorption; microchip electrophoresis; capillary electrophoresis; mass spectrometry}},
language = {{eng}},
number = {{1}},
pages = {{343--348}},
publisher = {{The American Chemical Society (ACS)}},
series = {{Analytical Chemistry}},
title = {{General approach for certain quantitative calculations for Instance of the variance of reversible adsorption to the capillary wall in CE}},
url = {{http://dx.doi.org/10.1021/ac8010457}},
doi = {{10.1021/ac8010457}},
volume = {{81}},
year = {{2009}},
}