Conference Posters



Joint Meeting of the Membrane Sections of the French and German Biophysical Societies" held on
April 11 - 14, 2016 in Bad Herrenalb, Germany.

"Novel protocols for protein purification by Free-FlowElectrophoresis"

AbstractPoster Berlin 2016 thmb

Free-flow electrophoresis (FFE), also known as ''carrier-free electrophoresis'', is an electrophoretic separation technique, which separates preparative and semi-preparative amounts of samples, ranging in size from metal ions to cells, according to minimal differences in charge and isoelectric point (pI). Because it is a matrix-free technique, that operates in standard buffer systems and allows for a cooled environment, it maximizes the preservation of protein activity and structural integrity of protein complexes and bio particles, leading also to high recovery rates. It is compatible with a wide range of electrophoretic modes, like isoelectric focusing (IEF) or interval zone electrophoresis (IZE), that allow for high resolution separation (< 0.02 ΔpH) with a high throughput (up to 3.5 mg protein/h) in short amounts of time (less than 10 minutes separation time). In the past this technique has proven to be useful for the separation of a lot of different samples including protein complexes, organelles, liposomes/vesicles, protein isoforms and nanodiscs.

 

 

 

 

 

 

 

Biologics & Biosimilars Congress, Berlin, 2016  and AT Europe 2016 in Vienna
"Three novel protocols for protein purification by Free-FlowElectrophoresis"

AbstractPoster Berlin 2016 thmb

A lot of clinically and scientifically relevant proteins, like monoclonal antibodies (mAB), undergo posttranslational modifications (PTM) stemming for example from glycosylation or mRNA splicing. These protein isoforms can differ from each other in their activity and therefore have to be closely studied and possibly separated from each other ahead of clinical application.
Here we present three complementary approaches for matrix-free separation of protein isoforms by Free Flow Electrophoresis (FFE). Its fast separation, high samplethroughput and -recovery make the FFE an ideal tool for semi-preparative separation of protein isoforms. All techniques allow for tailor-made separation conditions to fit the needs of the operator and the protein samples, to ensure native separation conditions.
The first technique (IEF-FFE) relies on a continuous separation, utilizing a pH-gradient generated by commercial ampholytes, which was used for preparative separation of monoclonal antibodies up to 100 mg with a throughput of 3 mg/h and a resolution of < 0.02 Δ-pH.
The second technique (ProLytesTM-FFE), matching handling, resolution and throughput of the first technique, makes use of a proprietary mixture of acids and bases to generate the pH-gradient needed for separation. Because no ampholytes encounter the samples, clinical application of the separated isoforms is possible.  
The third technique (IZE-FFE) relies on differences of electromigration in a stepwise pH-gradient, formed by the use of different acid and base containing buffers over the width of the separation chamber. Because the proteins are not separated at their isoelectric point, this technique minimizes protein-protein interactions and its short interval time of 10 minutes and throughput of up to 100 µg protein per interval, allows for high throughput analysis or preparation of samples by continuous collection of fractions.
Because of their high resolution and collection of significant amounts of sample, these techniques can be used as a preparative extension for capillary electrophoresis (CE) or other analytical techniques for further characterization of protein isoforms by MS or potency assays. 

 

CE-Pharm Meeting, New York,  2015
"Quantitative Separation of Protein Isoforms by Free Flow Electrophoresis"Poster IEF CE Pharm 2015thm

Abstract

Protein isoforms are defined as variants of a single polypeptide which generally alter its function. More than 90% of naturally occurring isoforms arise from post translational modifications (PTMs) and less than 10% from mRNA splice variations. In many cases, PTMs change the biological activity of proteins. Therefore their properties have to be closely studied before being administered as a drug.

Here, we introduced Continuous Horizontal Isolelectric Focussing Free Flow Electrophoresis (CHIEF-FFE) to isolate up to 100 milligram amounts of individual protein isoforms of mABs under native conditions that enable further biological studies. Resulting fractions were well suited for direct use in further studies such as enzyme- and/or immune-assays.

In contrast to competing technologies like capillary electrophoresis (CE) and imaged capillary isoelectric focusing (iCIEF) we are able to separate semi-preparative amounts of protein in a very fast workflow.

Variable lengths of electromigration and a variable span of pH, generated by using homemade ampholytes, gives us total control over protein separation. Zooming into ultra-flat pH gradients resulted in a resolution of 0.02 ∆pI between single fractions. Combined with rapid UV detection we were hereby able to separate and characterize multiple isoforms of different samples in quantitative amounts.


 

CE-Pharm Meeting, New York. 2015
"Novel iZE Separation Of Monoclonal Antibody Isoforms By Free Flow Electrophoresis"

Poster IZE CE Pharm 2015

Abstract

A lot of clinically and scientifically relevant proteins, like monoclonal antibodies (mAB), undergo posttranslational modifications (PTM) stemming for example from glycosylation or mRNA splicing. These protein isoforms can differ from each other in their activity and therefore have to be closely studied and possibly separated from each other ahead of clinical application.

The matrix-free separation of these proteins by Free Flow Electrophoresis (FFE) with its fast separation, high sample-throughput and -recovery make the FFE an ideal tool for semi-preparative separation of protein isoforms.

In a different approach we demonstrated the separation of mAB isoforms by Continuous Horizontal Isoelectric Focusing FFE (CHIEF-FFE). Here the protein isoforms were separated in an electrical field, by using an ampholyte containing buffer, to establish a continuous pH gradient. This approach results in a resolution of 0.02 ∆pI between single fractions and was therefore very well suited for isolation of single isoforms.

In a novel approach mAB isoforms were separated by FFE in interval zone electrophoresis (iZE) mode. The buffers used for interval zone only contain well defined chemicals (one acid, one base and mannitol) and no polymers or ampholytes to form a stepwise pH gradient. Thus, this technique is compatible for direct clinical and pre-clinical applications or crystallography.


 

PEGS Europe, Lisbon, 2015
"Three novel protocols for protein purification by Free Flow Electrophoresis"

Poster Lissabon

Abstract

A lot of clinically and scientifically relevant proteins, like monoclonal antibodies (mAB), undergo posttranslational modifications (PTM) stemming for example from glycosylation or mRNA splicing. These protein isoforms can differ from each other in their activity and therefore have to be closely studied and possibly separated from each other ahead of clinical application.

Here we present three complementary approaches for matrix-free separation of protein isoforms by Free Flow Electrophoresis (FFE). Its fast separation, high sample-throughput and -recovery make the FFE an ideal tool for semi-preparative separation of protein isoforms. All techniques allow for tailor-made separation conditions to fit the needs of the operator and the protein samples, to ensure native separation conditions.

The first technique (IEF-FFE) relies on a continuous separation, utilizing a pH-gradient generated by commercial ampholytes, which was used for preparative separation of monoclonal antibodies up to 100 mg with a throughput of 3 mg/h and a resolution of < 0.02 Δ-pH.

The second technique (ProLytesTM-FFE), matching handling, resolution and throughput of the first technique, makes use of a proprietary mixture of acids and bases to generate the pH-gradient needed for separation. Because no ampholytes encounter the samples, clinical application of the separated isoforms is possible.

The third technique (IZE-FFE) relies on a stepwise pH-gradient, formed by the use of different acid and base containing buffers over the width of the separation chamber. Because the proteins are not separated at their isoelectric point, this technique minimizes protein-protein interactions and its short interval time of 10 minutes and throughput of up to 100 µg protein per interval, allows for high throughput analysis or preparation of samples by continuous collection of fractions.

Because of their high resolution and collection of significant amounts of sample, these techniques can be used as a preparative extension for capillary electrophoresis (CE) or other analytical techniques for further characterization of protein isoforms by MS or potency assays.


 Application Notes

Prefractionation of E. coli lysates by free-flow electrophoresis for subsequent analysis by two-dimensional electrophoresis

Guideline for the enrichment of proteins from FFE-fractions

Separation of a protein mixture by free-flow electrophoresis with special focus on the day-to-day reproducibility

Native FFE Fractionation of human serum

Fractionation of Saccharomyces cervisiae proteins in 8M urea by isoelectric focusing free-flow electrophoresis

Isolation of peroxisome subpopulations from rat liver by immune free-flow electrophoresis

Fractionation of human serum proteins by free-flow electrophoresis: Workday-stability of the fractionation pattern

Combination of ProMetHEUS™ FFE with SDS-PAGE for the twodimensional separation of mitochondrial membrane proteins


Publications

Monoclonal Antibodies (mABs):

Brian D. Hosken, Charlene Li, Berny Mullappally, Carl Co, and Boyan Zhang. "Isolation and Characterization of Monoclonal Antibody Charge Variants by Free Flow Isoelectric FocusingAnalytical Chemistry DOI: 10.1021/acs.analchem.5b03946

Organelles:

de Michele R, McFarlane HE, Parsons HT, Meents MJ, Lao J, González Fernández-Niño SM, Petzold CJ, Frommer WB, Samuels AL, Heazlewood JL. "Free-Flow Electrophoresis of Plasma Membrane Vesicles Enriched by Two-Phase Partitioning Enhances the Quality of the Proteome from Arabidopsis Seedlings." J Proteome Res. 2016 Feb 4. [Epub ahead of print]

Parsons HT, Weinberg CS, Macdonald LJ, Adams PD, Petzold CJ, Strabala TJ, Wagner A, Heazlewood JL. “Golgi enrichment and proteomic analysis of developing Pinus radiata xylem by free-flow electrophoresis.” PLoS One. 2013 Dec 26;8(12):e84669

Parsons HT, Fernández-Niño SM, Heazlewood JL. “Separation of the plant Golgi apparatus and endoplasmic reticulum by free-flow electrophoresis.” Methods Mol Biol. 2014;1072:527-39

Schulz S, Schmitt S, Wimmer R, Aichler M, Eisenhofer S, Lichtmannegger J, Eberhagen C, Artmann R, Tookos F, Walch A, Krappmann D, Brenner C, Rust C, Zischka H. “Progressive stages of mitochondrial destruction caused by cell toxic bile salts.” Biochim Biophys Acta. 2013 Sep;1828(9):2121-33

Bussell JD, Behrens C, Ecke W, Eubel H. “Arabidopsis peroxisome proteomics.” Front Plant Sci. 2013 Apr 24;4:101

Parsons HT, Drakakaki G, Heazlewood JL. “Proteomic dissection of the Arabidopsis Golgi and trans-Golgi network.” Front Plant Sci. 2013 Jan 3;3:298

Islinger M, Abdolzade-Bavil A, Liebler S, Weber G, Völkl A. “Assessing heterogeneity of peroxisomes: isolation of two subpopulations from rat liver.” Methods Mol Biol. 2012;909:83-96

Islinger M, Li KW, Loos M, Liebler S, Angermüller S, Eckerskorn C, Weber G, Abdolzade A, Völkl A. “Peroxisomes from the heavy mitochondrial fraction: isolation by zonal free flow electrophoresis and quantitative mass spectrometrical characterization.” J Proteome Res. 2010 Jan;9(1):113-24

Braun RJ, Kinkl N, Zischka H, Ueffing M. “16-BAC/SDS-PAGE analysis of membrane proteins of yeast mitochondria purified by free flow electrophoresis.” Methods Mol Biol. 2009;528:83-107

Eubel H, Meyer EH, Taylor NL, Bussell JD, O'Toole N, Heazlewood JL, Castleden I, Small ID, Smith SM, Millar AH. “Novel proteins, putative membrane transporters, and an integrated metabolic network are revealed by quantitative proteomic analysis of Arabidopsis cell culture peroxisomes.” Plant Physiol. 2008 Dec;148(4):1809-29

Zischka H, Larochette N, Hoffmann F, Hamöller D, Jägemann N, Lichtmannegger J, Jennen L, Müller-Höcker J, Roggel F, Göttlicher M, Vollmar AM, Kroemer G “Electrophoretic analysis of the mitochondrial outer membrane rupture induced by permeability transition.”. Anal Chem. 2008 Jul 1;80(13):5051-8

Islinger M, Weber G. ”Free flow isoelectric focusing : a method for the separation of both hydrophilic and hydrophobic proteins of rat liver peroxisomes.” Methods Mol Biol. 2008;432:199-215

Eubel H, Lee CP, Kuo J, Meyer EH, Taylor NL, Millar AH. “Free-flow electrophoresis for purification of plant mitochondria by surface charge.” Plant J. 2007 Nov;52(3):583-94

Zischka H, Braun R J, et al “Differential analysis of Saccharomyces cerevisiae mitochondria by free-flow electrophoresis” Mol Cell Proteomics, Aug. 17. (2006)

Prokisch, H, Scharfe C "Integrative analysis of the mitochondrial proteome in yeast." PLoS Biol, 2(6): e160 (2004)

 Zischka H, Weber G, Weber PJ, Posch A, Braun RJ, Buhringer D, Schneider U, Nissum M, Meitinger T, Ueffing M, Eckerskorn C "Improved proteome analysis of Saccharomyces cerevisiae mitochondria by free-flow electrophoresis." Proteomics, Jun; 3(6): 906-16 (2003)

Mohr H, Voelkl A "Isolation of peroxisomal subpopulations from mouse liver by immune free-flow electrophoresis." Electrophoresis, Jul; 23(13):2130-7 (2002)

Voelkl A, Mohr H and Fahimi HD "Peroxisome subpopulations of the rat liver. Isolation by immune free flow electrophoresis.” J Histochem Cytochem 47(9), 1111-1118, (1999)

Voelkl A, Mohr H, Weber G and Fahimi HD "Isolation of peroxisomes subpopulations from rat liver by immune free flow electrophoresis." Electrophoresis, 19, 1140-1144, (1998)

Voelkl A, Mohr H, Weber G and Fahimi HD "Isolation of rat hepatic peroxisomes by means of Immune-Free Flow Electrophoresis." Electrophoresis, 18, 774 - 780 (1997)

Fuchs R, Male P, Mellman I "Acidification and Ion Permeabilities of highly purified Rat Liver Endosomes." Journal of Biol. Chem., 264 (No4), 2212-2220, (1989)

Marsh M "Endosome and lysosome purification by free-flow electrophoresis." Methods in Cell Biology, 31(), 319-334, (1989)

Schmid S and Mellman I "Isolation of functionally distinct endosome subpopulations by free-flow electrophoresis." In: Cell Free Analysis of Membrane Transport (Editors: D.J.Morre, K.E.Howell and G.M.W.Cook) A.R.Liss, New York, pp. 35-49 (1988)

 Marsh M, Kern H, Harms E, Schmid S, Mellman I and Helenius A "Co-fractionation of BHK-21 cell endosomes and lysosomes by free-flow electrophoresis." Prog.Clin.Biol.Res., 270, 21-33 (1988)

 

Proteines, Membrane Proteines und Peptides

Eichacker LA, Weber G, Sukop-Köppel U, Wildgruber R. “Free flow electrophoresis for separation of native membrane protein complexes.” Methods Mol Biol. 2015;1295:415-25.

Brotherton MC, Racine G, Ouellette M. “Separation of basic proteins from Leishmania using a combination of Free flow electrophoresis (FFE) and 2D electrophoresis (2-DE) under basic conditions.” Methods Mol Biol. 2015;1201:247-59

Wildgruber R, Weber G, Wise P, Grimm D, Bauer J. “Free-flow electrophoresis in proteome sample preparation.” Proteomics. 2014 Mar;14(4-5):629-36

Abu Shehab M, Iosef C, Wildgruber R, Sardana G, Gupta MB. “Phosphorylation of IGFBP-1 at discrete sites elicits variable effects on IGF-I receptor autophosphorylation.” Endocrinology. 2013 Mar;154(3):1130-43

Ma X, Wildgruber R, Bauer J, Weber G, Infanger M, Grosse J, Grimm D. “The use of sigmoid pH gradients in free-flow isoelectric focusing of human endothelial cell proteins.” Electrophoresis. 2012 May;33(9-10):1349-55

Fung KY, Cursaro C, Lewanowitsch T, Cosgrove L, Hoffmann P. “A combined free flow electrophoresis and DIGE approach to compare proteins in complex biological samples.” Methods Mol Biol. 2012;869:135-46

Fung KY, Cursaro C, Lewanowitsch T, Brierley GV, McColl SR, Lockett T, Head R, Hoffmann P, Cosgrove L. “A combined free-flow electrophoresis and DIGE approach to identify proteins regulated by butyrate in HT29 cells.” Proteomics. 2011 Mar;11(5):964-71

Brotherton MC, Racine G, Foucher AL, Drummelsmith J, Papadopoulou B, Ouellette M. “Analysis of stage-specific expression of basic proteins in Leishmania infantum.” J Proteome Res. 2010 Aug 6;9(8):3842-53

Sneekes EJ, Han J, Elliot M, Ausio J, Swart R, Heck AJ, Borchers C. “Accurate molecular weight analysis of histones using FFE and RP-HPLC on monolithic capillary columns.” J Sep Sci. 2009 Aug;32(15-16):2691-8

Nissum M, Abu Shehab M, Sukop U, Khosravi JM, Wildgruber R, Eckerskorn C, Han VK, Gupta MB. “Functional and complementary phosphorylation state attributes of human insulin-like growth factor-binding protein-1 (IGFBP-1) isoforms resolved by free flow electrophoresis.” Mol Cell Proteomics. 2009 Jun;8(6):1424-35

Braun RJ, Kinkl N, Beer M, Ueffing M. “Two-dimensional electrophoresis of membrane proteins.” Anal Bioanal Chem. 2007 Oct;389(4):1033-45

“Optimized Peptide Separation and Identification for Mass Spectrometry Based Proteomics via Free-Flow Electrophoresis” Johan Malmström, Hookeun Lee, Alexey I. Nesvizhskii, David Shteynberg, Sonali Mohanty, Erich Brunner, Mingliang Ye, Gerhard Weber, Christoph Eckerskorn, and Ruedi Aebersold J. Proteome Res.; 2006; 5(9) pp 2241 - 2249

Immler D, Greven S, Reinemer P „Targeted proteomics in biomarker validation: Detection and quantification of proteins using a multi-dimensional peptide separation strategy“ Proteomics, 6, 2947-2958 (2006)

Moritz RL, Skandarajah A., Ji H, Simpson RJ “Proteomic analysis of colorectal cancer: prefractionation strategies using two-dimensional free-flow electrophoresis” Comparative and Functional Genomics, 6, 236-243 (2005)

Xie H, Rhodus NL, Griffin RJ, Carlis JV, Griffin TJ “A Catalogue of Human Saliva Proteins Identified by Free Flow Electrophoresis-based Peptide Separation and Tandem Mass Spectrometry” Mol Cell Proteomics 4(11): 1026-30 (2005)

Grimm, D. et. al "Free-flow isoelectric focusing of proteins remaining in cell fragments following sonication of thyroid carcinoma cells." Electrophoresis, 26(11): 2109-16 (2005)

Xie H, Bandhakavi S, Griffin TJ “Evaluating preparative isoelectric focusing of complex peptide mixtures for tandem mass spectrometry-based proteomics: a case study in profiling chromatin-enriched subcellular fractions in Saccharomyces cerevisiae Anal Chem, 15;77(10): 3198-107 (2005)

Hoffmann P, Olayioye MA "Breast cancer protein StarD10 identified by three-dimensional separation using free-flow electrophoresis, reversed-phase high-performance liquid chromatography, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis." Electrophoresis, 26(6): 1029-37 (2005)

Weber G, Islinger M, Weber P, Eckerskorn C, Voelkl A "Efficient separation and analysis of peroxisomal membrane proteins using free-flow isoelectric focusing." Electrophoresis, Jun;25(12):1735-47 (2004)

 Moritz RL, Ji H, Schutz F, Connolly LM, Kapp EA, Speed TP, Simpson RJ "A Proteome Strategy for Fractionating Proteins and Peptides Using Continuous Free-Flow Electrophoresis Coupled Off-Line to Reverse-Phase High Performance Liquid Chromatography." Analytical Chemistry, 76: 4811-4824 (2004)

Hoffmann P, Ji H, Moritz RL, Connolly LM, Frecklington DF, Layton MJ, Eddes JS and Simpson RJ "Continuous free-flow electrophoresis separation of cytosolic proteins from the human colon carcinoma cell line LIM 1215: A non two-dimensional gel electrophoresis-based proteome analysis strategy." Proteomics, 1, 807-818 (2001)

Bardy N, Carrasco A, Galaud J PH, Pont Lezica R and Canut H "Free-flow Electrophoresis for fractionation of Arabidopsis thaliana membranes." Electrophoresis, 19, 1145-1153 (1998)

Bauer J and Weber G "Interval carrier free electrophoresis for high resolution protein purification." J. Disp. Sci. Tech., 19 937-950 (1998)

Lasch J, Moschner S, Sann H, Zellmer S and Koelsch R "Aminopeptidase P - a cell surface antigen of Endothelial and Lymphoid Cells: Catalytical and Immuno-Histotopical Evidences." Biol. Chem., Vol 379, 705-709 (1998)

Murer H, Gmaj P, Stieger B and Hagenbuch B "Transport studies with renal proximal tubular and small intestinal Brush border and Basolateral Membrane vesicles: Vesicles heterogeneity, Coexistence of Transport systems." Meth. Enzymol., 172, 346-364, (1989)

Morre DJ, Nowack D, Paulik M, Brightman AO, Thornbrough K, Yim, J and Auderset G "Transitional endoplasmic reticulum membranes and vesicles isolated from animals and plants. Homologous and Heterologous transfer to Golgi apparatus." Protoplasma, 153, 1-13, (1989)

Holzenburg A, Engel A, Kessier R, Manz HJ, Lustig A and Aebi U "Rapid isolation of OmpF Porin-LPS complexes." Biochemistry, 28,4187 (1989) Human Plasma, Urine and Body Fluids

 Gaillard G, Trezzi JP, Betsou F. “Validation of free flow electrophoresis as a novel plasma and serum processing and fractionation method in biobanking.” Biopreserv Biobank. 2012 Aug;10(4):349-56

Foucher AL, Craft DR, Gelfand CA. “Application of free flow electrophoresis to the analysis of the urine proteome.” Methods Mol Biol. 2010;641:27-45

Foucher AL, Hartmann K, Hauptmann M, Wildgruber R, Safinowski M, Forst T, Pfützner A, Gelfand CA, Nissum M. “Resolution of adiponectin oligomers in human plasma using free flow electrophoresis.” Arch Physiol Biochem. 2009 Dec;115(5):267-78

Tunica DG, Yin X, Sidibe A, Stegemann C, Nissum M, Zeng L, Brunet M, Mayr M. “Proteomic analysis of the secretome of human umbilical vein endothelial cells using a combination of free-flow electrophoresis and nanoflow LC-MS/MS.” Proteomics. 2009 Nov;9(21):4991-6

 Nissum M, Foucher AL. “Analysis of human plasma proteins: a focus on sample collection and separation using free-flow electrophoresis.” Expert Rev Proteomics. 2008 Aug;5(4):571-87

Nissum M, Wildgruber R. “Free-flow electrophoresis of the human urinary proteome.” Methods Mol Biol. 2008;484:131-44

Wildgruber R, Yi J, Nissum M, Eckerskorn C, Weber G. “Free-flow electrophoresis system for plasma proteomic applications.” Methods Mol Biol. 2008;424:287-300

Nissum M, Kuhfuss S, Hauptmann M, Obermaier C, Sukop U, Wildgruber R, Weber G, Eckerskorn C, Malmström J. “Two-dimensional separation of human plasma proteins using iterative free-flow electrophoresis.” Proteomics. 2007 Dec;7(23):4218-27

Moritz RL et al. “Application of 2-D free flow electrophoresis/RP-HPLC for proteomic analysis of human plasma depleted of multi high-adundance proteins” Proteomics, 5(13): 3402-13 (2005)

Sang Yun Cho, Eun-Young Lee, Joon Seok Lee, Young-Ki Paik et al. “Efficient prefractionation of low-abundance proteins in human plasma and construction of a two-dimensional map” Proteomics, 5, 3386-3396 (2005)


Clinical Applications

Pereira de Souza T, Holzer M, Stano P, Steiniger F, May S, Schubert R, Fahr A, Luisi PL “New Insights into the Growth and Transformation of Vesicles: A Free-Flow Electrophoresis Study.” J Phys Chem B. 2015 Sep 17;119(37):12212-23

Neustadt M, Costina V, Kupfahl C, Buchheidt D, Eckerskorn C, Neumaier M, Findeisen P. “Characterization and identification of proteases secreted by Aspergillus fumigatus using free flow electrophoresis and MS.” Electrophoresis. 2009 Jun;30(12):2142-50

Moritz RL, Skandarajah AR, Ji H, Simpson RJ. “Proteomic analysis of colorectal cancer: prefractionation strategies using two-dimensional free-flow electrophoresis.” Comp Funct Genomics. 2005;6(4):236-43

Schneiderman E, Gratz SR, Stalcup AM "Optimization of preparative electrophoretic chiral separation of ritalin enantiomers." J Pharm Biomed Anal, 27, p: 639-50 (2002)

Wind M, Hoffmann P, Wagner H Thormann W "Chiral capillary electrophoresis as a predictor for separation of drug enantiomers in continuous flow zone electrophoresis." Journal of Chromatography A, 895, 51-65 (2000)

Wind M, Hoffmann P, Wagner H Thormann W "Chiral capillary electrophoresis as a predictor for separation of drug enantiomers in continuous flow zone electrophoresis." Journal of Chromatography A, 895, 51-65 (2000)

Hoffmann P, Wagner H, Weber G, Lanz M, Caslavska J and Thormann W "Separation and Purification of Methadone Enantiomers by Continuous- and Interval-Flow Electrophoresis." Analytical Chemistry, 71(9); 1840-1850 (1999) Cell separation

Heidrich, H.G. and Hannig, K. (1989) Separation of cell populations by free-flow electrophoresis. Methods Enzymol. 171, 513–531.

Hansen E, Wustrow Pu and Hannig K "Antigen-Specific Electrophoretic Cell Separation for Immunological Investigations." Electrophoresis, 10 (8-9), 645-652, (1989)

Baier TG, Weber G, Hartmann K, Heinrich U, Schönberg D "Preparative separation of human-b and lymphocytes-t by free-flow electrophoresis." Analytical Biochemistry, 171(N1), 91-95, (1988)

Bauer J, Kachel V and Hannig K "The negative surface charge density is a maturation marker of human B-lymphocytes." Cellular Immunology, 111: 354-364 (1988)


Nano Particels

Timm C, Niemeyer CM. “Assembly and purification of enzyme-functionalized DNA origami structures.” Angew Chem Int Ed Engl. 2015 Jun 1;54(23):6745-50

Justesen BH, Laursen T, Weber G, Fuglsang AT, Møller BL, Pomorski TG. “Isolation of monodisperse nanodisc-reconstituted membrane proteins using free flow electrophoresis.” Anal Chem. 2013 Apr 2;85(7):3497-500. doi: 10.1021/ac4000915. Epub 2013 Mar 11.

Rachel R. Peterson and David E. Cliffel "Continuous Free-Flow Electrophoresis of Water-Soluble Monolayer-Protected clusters." Anal. Chem, 77, 4348 - 4353 (2005)

 

General Publications

Islinger M, Eckerskorn C, Völkl A. “Free-flow electrophoresis in the proteomic era: a technique in flux.” Electrophoresis. 2010 Jun;31(11):1754-63

Ouvry-Patat SA, Torres MP, Gelfand CA, Quek HH, Easterling M, Speir JP, Borchers CH. “Top-down proteomics on a high-field Fourier transform ion cyclotron resonance mass spectrometer.” Methods Mol Biol. 2009;492:215-31

Ouvry-Patat SA, Torres MP, Quek HH, Gelfand CA, O'Mullan P, Nissum M, Schroeder GK, Han J, Elliott M, Dryhurst D, Ausio J, Wolfenden R, Borchers CH. “Free-flow electrophoresis for top-down proteomics by Fourier transform ion cyclotron resonance mass spectrometry.” Proteomics. 2008 Jul;8(14):2798-808

Weber G, Wildgruber R. “Free-flow electrophoresis system for proteomics applications.” Methods Mol Biol. 2008;384:703-16

Malmström J, Lee H, Nesvizhskii AI, Shteynberg D, Mohanty S, Brunner E, Ye M, Weber G, Eckerskorn C, Aebersold R. “Optimized peptide separation and identification for mass spectrometry based proteomics via free-flow electrophoresis.” J Proteome Res. 2006 Sep;5(9):2241-9

Moritz RL and Simpson RJ “Liquid-based free-flow electrophoresis-reversed-phase HPLC: a proteomic tool” NAT Methods, 2(11): 863-73 (2005)

Wang Y, Hancock WS, Weber G, Eckerskorn C, Palmer-Toy D "Free flow electrophoresis coupled with liquid chromatography-mass spectrometry for a proteomic study of the human cell line (K562/CR3)." Journal of Chromatography A, 1053: 269-278 (2004)

Krivankova L and Bocek P "Continuous free flow electrophoresis." Electrophoresis, 19, 1064-1074 (1998)

Song JF, Liu X, Shen A, Gao-de W and Qi-chang X "Application of Free Flow Electrophoresis to the purification of trichosanthin from a crude product of acetone fractional precipitation." Electrophoresis, 19 1097-1103 (1998)

Weber G and Bauer J "Counterbalancing hydrodynamic sample distortion effects increases resolution of free flow zone electrophoresis." Electrophoresis, 19, 1104-1109 (1998)

Weber G and Bocek P "Recent developments in preparative free flow isoelectric focusing." Electrophoresis, 19, 1649 - 1653 (1998)

Heidrich HG
"Free-flow particle electrophoresis in cell biology and biochemistry - an updated review."
In: Electrophoresis '88, Proceedings of the Sixth Meeting of The International Electrophoresis Society, July 1988, Copenhagen (Ed.: C.Schafer-Nielseri) VCH Verlags. GmbH, Weinheim, FRG. pp. 187-200. (1988)

Morre DJ "Free-flow electrophoresis: Preparative applications to cell-free analysis of exocytic membrane traffic." In: Cell Free Analysis of Membrane Transport (Editors: D.J. Morre, K.E.Howell and G.M.W.Cook) A.R.Liss, New York, pp. 7-19 (1988)