Thermoresponsive Agarose Based Microparticles for Antibody Separation

Area of Science:

• Chromatography
• Bioseparation
• Polymer Science

Background:

• Antibody purification is crucial in biopharmaceutical manufacturing.
• Existing methods often lack efficient, switchable release mechanisms.
• Thermoresponsive polymers offer tunable properties for separation applications.

Purpose of the Study:

• To develop novel thermoresponsive chromatographic resins for antibody separation.
• To engineer resins with switchable adsorption and release capabilities.
• To investigate the impact of polymer properties on separation performance.

Main Methods:

• Grafting of linear poly(N-isopropylacrylamide) (PNIPAM) chains onto microsphere resins.
• Modification of PNIPAM chains with 4-mercaptoethylpyridine (MEP) end functionalities.
• Synthesis of PNIPAM via reversible addition-fragmentation chain transfer (RAFT) polymerization.
• Evaluation of antibody (γ-globulin) binding and release at different temperatures (40°C and 5°C).

Main Results:

• Developed MEP-based thermoresponsive resins exhibiting switchable antibody binding.
• Achieved high binding capacities (up to 20 g L⁻¹) at 40°C and significantly reduced capacity (<2.5 g L⁻¹) at 5°C.
• Demonstrated efficient antibody release (up to 90%) upon temperature reduction to 5°C.
• Showed that polymer chain length critically influences MEP functionality density and binding capacity.

Conclusions:

• The developed thermoresponsive PNIPAM-MEP resins provide a promising platform for switchable antibody separation.
• Temperature-dependent adsorption and release offer a controllable and efficient purification strategy.
• Optimization of polymer chain length is key to maximizing binding capacity and separation efficiency.