Ion Exchange Chromatography (IEX) Technology

Ion exchange chromatography (IEX) is the most widely used high-throughput analytical technique for producing pure proteins. CD Formulation integrates cutting-edge IEX technology into our protein characterization technology platform to provide reliable analytical support for all stages of the development and production of your protein/peptide drugs, including formulation development, process development, drug release testing, and stability testing.

What is Ion Exchange Chromatography (IEX) Technology?

IEX is a chromatographic technique that separates mixtures of proteins or peptides based on differences in their net surface charge. The technique does not require organic solvents and is therefore often used to characterize proteins in their native/active form. IEX involves the interaction between a charged stationary phase and an oppositely charged mobile analyte. An appropriate column, buffer pH, and salt concentration are key factors in the success of IEX.

Ion Exchange Chromatography (IEX) Principle

The principle of IEX separation is based on the unique net surface charge of each protein at any given pH. This property is exploited to separate molecules by releasing them from the column by changing the pH or ionic strength of the mobile phase, based on their interaction with oppositely charged particles in the stationary phase. In cation exchange chromatography, positively charged molecules are attracted to the negatively charged stationary phase. Similarly, in anion exchange chromatography, negatively charged molecules are attracted to the positively charged stationary phase.

Fig. 1 The principle of IEX Separation. (Salvato F, et al., 2012)

Our Services Related to Ion Exchange Chromatography (IEX)

Thanks to decades of experience supporting protein/peptide biopharmaceutical development and manufacturing using IEX technology, our team of highly qualified experts offers a range of IEX-related services to accelerate the implementation and success of your project.

Our experienced team of experts has completed hundreds of IEX separation and purification projects for protein and peptide, supporting all stages of your protein/peptide drug development and manufacturing - from early studies to downstream process monitoring and GMP batch release testing.

Utilizing cutting-edge IEX technology, we support the following protein/peptide development and characterization plans, including but not limited to:

Protein/Peptide Purification

IEX can effectively separate proteins based on their net charge, which is affected by the pH and ionic strength of the buffer. This allows for the purification of specific proteins from complex biological mixtures.

Protein/Peptide Characterization

• pI Determination: IEX is performed at different pH levels to infer the isoelectric point (pI) of a protein.
• Charge Variant Analysis: Separate and analyze different charge variants of a protein that may arise from post-translational modifications such as phosphorylation or glycosylation, thereby identifying product heterogeneity in size and charge.

Biophysical Characterization

• Assessing Protein Stability: Understand protein stability and folding by analyzing how the protein behaves under different conditions, such as changes in ionic strength or pH.
• Interaction Studies: Study protein-protein and protein-ligand interactions based on charge variations and electrostatic interactions.

Procedure for Ion Exchange Chromatography (IEX) Analysis

• The protein sample is loaded into an ion exchange chromatography column at a specific pH.
• Charged proteins bind to oppositely charged functional groups in the resin.
• A salt gradient is used to elute the separated proteins.
  • At low salt concentrations, proteins with fewer charged groups are eluted.
  • At high salt concentrations, proteins with more charged groups are eluted.
• Washing the column removes unwanted proteins and impurities.
  • A decreasing pH gradient is used to elute proteins from an anion exchange resin.
  • An increasing pH gradient is used to elute proteins from a cation exchange resin.

Our Equipment

With many years of experience performing IEX analyses, we are happy to apply our expertise to develop a tailor-made IEX method for you. Our analytical laboratory is equipped with high-performance size exclusion chromatography (HP-IEX) with the following detectors to support the separation and purification of protein-based therapeutics.

• UV detector.
• Fluorescence detector.
• Multi-angle laser light scattering (MALLS) detector.

Advantages of Ion Exchange Chromatography (IEX) Technology

• High resolution.
• One of the most versatile liquid chromatography techniques.
• IEX is performed under non-denaturing conditions, suitable for characterizing proteins in their native/active form.
• IEX can effectively separate proteins with different charges to achieve high purity.
• IEX can purify large volumes of products and has the potential to obtain concentrated products in fairly small volumes.
• IEX can be applied to a wide range of proteins and peptides, adapting to various types of samples, from small-scale research to large-scale protein production.
• IEX is compatible with different buffers.

Custom Ion Exchange Chromatography (IEX) Services

Why Choose Our Ion Exchange Chromatography (IEX) Technology?

• We have a team of experts with rich experience in IEX analytical method development and validation.
• We have accumulated decades of expertise and successful project experience using IEX technology to support protein/peptide biopharmaceutical development.
• Our IEX technology provides exceptional resolution and selectivity, allowing for the effective separation of proteins based on their charge properties.
• Our laboratories are equipped with cutting-edge IEX equipment and detection technologies, enabling innovative methodologies and high-quality data generation.
• We provide end-to-end support, from sample preparation to data interpretation, to help you make informed decisions based on our results.
• We adhere to strict quality control and regulatory standards to ensure the integrity and compliance of your data.
• We provide flexible experimental design and customized solutions.

Publication

CD Formulation aims to provide a powerful analytical tool for the separation, purification, and characterization of proteins and peptides. Please feel free to contact us if you are interested in our services. Learn how our IEX technology can support the smooth implementation of your protein/peptide biopharmaceutical program.

How It Works

STEP 1

Submit a service request describing your specific research or development need.

STEP 2

We'll email you to provide your quote and confirm order details if applicable.

STEP 3

Execute the project with real-time communication, and deliver the final report promptly.