Alginate–modified sensor chips
XanTec’s alginate (AL) sensor chips are based on a 50 nm alginate hydrogel matrix grafted onto a hydrophilic adhesion promoter on a gold support. The negatively charged carboxyl groups distributed along the polysaccharide chains enable efficient electrostatic preconcentration of ligands prior to covalent coupling.
Ligands can be covalently attached through their amine, thiol, or aldehyde groups using standard coupling chemistries such as EDC/NHS activation, thiol–maleimide conjugation, or reductive amination. This allows immobilization of proteins, antibodies, peptides, nucleic acids, and small molecules. Efficient protein immobilization requires electrostatic preconcentration before covalent attachment.
XanTec’s AL sensor chips were specifically developed as a functionally equivalent alternative to Bio-Rad’s ProteOn GLM sensor chips. They provide ProteOn users with a compatible alginate-based hydrogel surface and represent a reliable option when CMD- or HC-based coatings are unsuitable or cannot be applied.
In addition, AL sensor chips serve as benchmark coatings for assessing nonspecific binding during the development and evaluation of biomedical and antifouling surface chemistries.
Key features:
- Alternative to ProteOn GLM sensor chips: Provides a 3D alginate-based hydrogel matrix for covalent ligand immobilization.
- Versatile ligand coupling: Supports amine-, thiol-, and aldehyde-based coupling using established chemistries (EDC/NHS, maleimide, reductive amination).
- Benchmark surface: Suitable as a reference coating for evaluating nonspecific binding and new biomedical coating materials.
| Product code | AL |
|---|---|
| Base coating | 3D, 50 nm alginate (medium density) |
| Electrostatic preconcentration capacity [µRIU]2 | ≈ 13,000 |
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1 All illustrations are schematic representations and are not drawn to scale; dimensions, densities, and spatial relationships do not reflect actual physical or chemical proportions.
2 Preconcentration capacity determined by injecting 100 µg/mL BSA in 5 mM sodium acetate pH 5.0, with 1 µRIU corresponding approximately to 1 RU. Maximum covalent coupling yields depend on ligand properties and typically range from approximately 20–45% of the respective electrostatic preconcentration capacity.