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Updated: Jul 17, 2026
08:29
Proteome-wide Quantification of Labeling Homogeneity at the Single Molecule Level
Published on: April 19, 2019
Multivalence and spot heterogeneity in microarray-based measurement of binding constants
Martin Elbs1, Michael Hulko, Jens Frauenfeld
1Ciba Specialty Chemicals, 4002, Basel, Switzerland.
Analytical and Bioanalytical Chemistry
|January 30, 2007
Summary
High-resolution imaging and segmentation of microarrays reveal ligand binding differences. Analyzing heterogeneous spots separately provides crucial data, especially for multivalent ligands, lost in whole-spot analysis.
Area of Science:
- Biotechnology
- Analytical Chemistry
- Surface Science
Background:
- Microarray technology enables miniaturized, parallel binding constant measurements.
- Heterogeneous surface functionalization is a common challenge in microarray experiments.
- Receptor density significantly impacts ligand binding, particularly for multivalent ligands.
Purpose of the Study:
- To investigate the impact of surface heterogeneity on ligand binding analysis in microarrays.
- To demonstrate the value of high-resolution imaging and image segmentation for accurate binding measurements.
- To compare binding behavior of monovalent and bivalent ligands on heterogeneous surfaces.
Main Methods:
- Utilized confocal microscopy for high-resolution imaging of microarrays.
- Applied image segmentation to analyze inhomogeneous spots separately (bright and dark areas).
- Performed binding titrations with monovalent and bivalent fluorescent ligand peptides against the vancomycin receptor.
Main Results:
- Spot heterogeneity affected monovalent ligand binding constants minimally.
- Bivalent ligand affinity was higher in denser receptor regions (bright areas) of heterogeneous spots.
- Analyzing spots as a whole masked the affinity differences observed in segmented areas.
Conclusions:
- High-resolution imaging and image segmentation are critical for accurate miniaturized binding assays.
- Surface receptor density heterogeneity significantly influences multivalent ligand binding.
- Detailed analysis of microarrays enhances understanding of molecular interactions.
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