Adsorption of Immunoglobulin G on Core-Shell Latex Particles Precoated with Chaps

Area of Science:

• Biomaterials Science
• Surface Chemistry
• Immunology

Background:

• Latex particles functionalized with chloromethyl groups are used for biomolecule immobilization.
• 3-([3-cholamidopropyl]dimethylammonio-1-propanesulfonate) (Chaps) is a zwitterionic surfactant used for surface modification.
• Monoclonal antibodies, such as immunoglobulin G (IgG), are critical in diagnostics and therapeutics.

Purpose of the Study:

• To investigate the adsorption mechanism of IgG onto Chaps-precoated latex particles with reactive chloromethyl groups.
• To determine the effect of temperature on Chaps displacement and IgG covalent bonding.
• To analyze the kinetics and thermodynamics of IgG adsorption.

Main Methods:

• Monitoring chloromethyl group reactivity via glycinate nucleophilic attack at different temperatures (22°C and 36°C).
• Quantifying Chaps displacement by IgG and determining the enthalpy of adsorption.
• Analyzing the two-step adsorption process involving physical interaction and covalent bonding.

Main Results:

• IgG adsorption proceeds in two distinct steps: a rapid, temperature-independent physical interaction followed by slower covalent bonding.
• Higher temperatures (36°C) favor Chaps desorption, exposing reactive sites.
• Elevated temperatures accelerate IgG covalent bonding to the latex surface.

Conclusions:

• The adsorption of IgG on Chaps-precoated latex is a two-step process influenced by temperature.
• Optimizing temperature enhances Chaps desorption and subsequent covalent immobilization of IgG.
• This understanding is crucial for developing effective antibody-based diagnostic and therapeutic platforms.