YMC’s BioPro is a Reliable Tool for Analyzing PEGylated Proteins

Ligand® Pharmaceuticals Inc. had an excellent success utilizing YMC’s BioProIEX to analyze PEGylated protein charge variants reproducibly. They developed a characterization method for PEGylated biotherapeutic proteins that can provide increased information without compromising peak shape and resolution and wanted to share their discovery with the broader industry. They reached out to YMC to gain support for the publication of a white paper detailing their method.

Recently published in the LCGC Journal, this paper educates the reader on:

The numerous positive attributes of PEGylated proteins.
Major techniques for determining the charge-variant analysis of proteins.
A characterization method for PEGylated biotherapeutic proteins that can provide increased information without compromising peak shape and resolutions.

Benefits and Analysis of PEGylated Protein Drugs

There are numerous advantages to creating PEGylated protein drugs, as they are bioinert, hydrophilic, and non-immunogenic, among many other positive qualities. PEGylated protein drugs also have increased half-life, which furthers their circulation life and lowers the frequency of doses needed to keep the drug active. Additionally, the PEG coating the protein can improve stability while reducing toxicity.

Analysis of the charge-variant of a protein is conducted using one of these three techniques:

Capillary Zone Electrophoresis (CZE)
Imaged Capillary Isoelectric Focusing (iCIEF)
Ion Exchange Chromatography (IEX)

Of these three methods, Imaged Capillary Isoelectric Focusing has become the industry standard and is performed with either the familiar salt gradient or the more recent pH gradient technique.

Challenges with Analyzing PEGylated Proteins

Unfortunately, as beneficial as PEG is for the effectiveness and stability of protein drugs, it is not without flaws. Analyzing PEGylated proteins can be difficult because the steric-bulk of the PEG residue is a detriment to the electrostatic interactions conducted between the charges surface of the IEX column and the amino acid residues of the protein.

How the BioPro can Help Analyze PEGylated Proteins

As the difficulties brought about by the presence of PEG hinder the analysis of proteins, scientists set out to find ways to remedy the problem. They saw YMC’s BioPro SF column as a solution to their setback and conducted an experiment to test its ability to analyze PEGylated protein charge variants reproducibly.

Through extensive experimentation, they discovered that the BioPro SF column was capable of increasing the information they received without losing the resolution and shape of the proteins. For example, the experiment demonstrated that the resolution and shape did not change during the over 100 injections they made in a single run.

With this newfound knowledge, other researchers can now implement the BioPro SF column into their operations to better confirm and analyze PEGylated proteins and their protein charge variants. Additionally, the BioPro SF column was found to also increase the pH results, offering a quicker retention time, as well as relative-area reproducibility.

If your organization is searching for high-quality ion exchange products, consult YMC America today. We also specialize in normal phase chromatography products and numerous other services.