Quantitative ligand immobilization using alginate hydrogel formed in a capillary: application for online affinity...

Area of Science:

• Biomaterials Science
• Analytical Chemistry
• Biotechnology

Background:

• Ligand immobilization is crucial for various biochemical assays and separations.
• Existing methods can be complex and may compromise ligand activity.
• A simplified, quantitative, and activity-preserving immobilization technique is needed.

Purpose of the Study:

• To develop an automated method for quantitative ligand immobilization.
• To maintain ligand activity during the immobilization process.
• To create a functionalized capillary for specific analyte capture and elution.

Main Methods:

• Utilized an alginate hydrogel formed in situ within a capillary.
• Employed electro-driven Ca(2+) introduction for controlled hydrogelation and ligand encapsulation.
• Assessed immobilization efficiency and ligand affinity using avidin-biotin binding capacity.
• Demonstrated analyte separation and elution by pH adjustment.

Main Results:

• Achieved nearly 100% immobilization efficiency for avidin.
• Demonstrated quantitative immobilization of 3.5-35.2 ng of avidin while preserving its affinity.
• Successfully trapped and separated biotinylated fluorescein using the avidin-immobilized capillary.
• Obtained 90% recovery of concentrated analytes with high reproducibility.

Conclusions:

• The developed automated method provides a simple and efficient way to immobilize ligands quantitatively.
• The alginate hydrogel capillary system effectively maintains ligand activity and enables specific analyte capture.
• This technique offers a promising platform for applications in biochemical analysis and purification.