Integrated Electrokinetic Sample Focusing and Surface Plasmon Resonance Imaging System for Measuring Biomolecular Interactions

Label-free biomolecular binding measurement methods, such as surface plasmon resonance (SPR), are becoming increasingly more important for the estimation of real-time binding kinetics. Recent advances in surface plasmon resonance imaging (iSPR) are emerging for label-free microarray-based assay appl...

Full description

Saved in:
Bibliographic Details
Published in:Analytical chemistry (Washington) 2009-03, Vol.81 (5), p.1957-1963
Main Authors: Krishnamoorthy, Ganeshram, Carlen, Edwin T, Kohlheyer, Dietrich, Schasfoort, Richard B. M, van den Berg, Albert
Format: Article
Language:English
Subjects:
Adsorption
Analytical chemistry
Biosensing Techniques - methods
Chemical bonds
Chemistry
Electrochemistry - methods
Exact sciences and technology
General, instrumentation
Immunoglobulins
Kinetics
Ligands
Molecular structure
Protein Binding
Protein Interaction Mapping - methods
Scientific imaging
Surface Plasmon Resonance - methods
Surface Properties
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Label-free biomolecular binding measurement methods, such as surface plasmon resonance (SPR), are becoming increasingly more important for the estimation of real-time binding kinetics. Recent advances in surface plasmon resonance imaging (iSPR) are emerging for label-free microarray-based assay applications, where multiple biomolecular interactions can be measured simultaneously. However, conventional iSPR microarray systems rely on protein printing techniques for ligand immobilization to the gold imaging surface and external pumps for analyte transport. In this article, we present an integrated microfluidics and iSPR platform that uses only electrokinetic transport and guiding of ligands and analytes and, therefore, requires only electrical inputs for sample transport. An important advantage of this new approach, compared to conventional systems, is the ability to direct a single analyte to a specific ligand location in the microarray, which can facilitate analysis parallelization. Additionally, this simple approach does not require complicated microfluidic channel arrangements, external pumps, or valves. As a demonstration, kinetics and affinity have been extracted from measured binding responses of human IgG and goat antihuman IgG using a simple 1:1 model and compared to responses measured with conventional pressure driven analyte transport. The measured results indicate similar binding kinetics and affinity between the electrokinetic and pressure-driven sample manipulation methods and no cross contamination to adjacent measurement locations has been observed.
ISSN:0003-2700
1520-6882
DOI:10.1021/ac802668z