This work presents several critical details for making cIEF-MALDI-MS a robust technique which will allow for more routine application and aid in automation. This includes emphasis on the hardware necessary for syringe pump mobilization and proper protocol for preventing disruption from gas bubbles. Following these guidelines, excellent elution time reproducibility is demonstrated for six pI mar...

Capillary electrophoresis (CE) techniques have been fundamental in advancing technology for the separation and identification of peptide and protein mixtures [1,2]. Today, they have become a staple in conjunction with mass spectrometry systems to resolve, identify and analyze protein and peptide characteristics with sensitivity and accuracy. Recent advances have miniaturized traditional CE inst...

Proteome-pI is an online database containing information about predicted isoelectric points for 5029 proteomes calculated using 18 methods. The isoelectric point, the pH at which a particular molecule carries no net electrical charge, is an important parameter for many analytical biochemistry and proteomics techniques, especially for 2D gel electrophoresis (2D-PAGE), capillary isoelectric focus...

The development of therapeutic proteins and peptides is an expensive and time-intensive process. Biologics, which have become a multi-billion dollar industry, are chemically complex products that require constant observation during each stage of development and production. Post-translational modifications along with chemical and physical degradation from oxidation, deamidation, and aggregation,...

Native Isoelectric Focusing Free-flow Electrophoresis (IEF-FFE) Fractionation of Crude Protein Mixtures Peter J.A. Weber, Gerhard Weber, and Christoph Eckerskorn This protocol was adapted from "Native IEF-FFE Fractionation of Crude Protein Mixtures," contributed by Peter J.A. Weber, Gerhard Weber, and Christoph Eckerskorn, Chapter 19, in Purifying Proteins for Proteomics (ed. Simpson). Cold Spr...

The technique previously applied to serum can, with minor modifications, be applied to cerebrospinal fluid. Good protein patterns have been obtained and similarities as well as differences have been demonstrated between cerebrospinal fluid and serum. The patterns obtained should prove useful in neurological diagnosis.

In order to examine the diversity of antibody light chains, we have developed an analytic isoelectric focusing procedure which permits the routine analysis of L chains from antibodies raised in individual mice. We have used this technique to demonstrate that the light chains of IgM and IgG anti-group A streptococcal antibodies raised in SWR mice are probably shared. Interestingly, numerous ligh...