Applications
Biochemical Applications >> Protein-Protein Binding
Protein-Protein direct binding assays are highly desirable in drug discovery campaigns, particularly those that are high throughput in nature and have simplified assay development. BIND® technology enables quantitative, label-free analysis of protein binding interactions producing information on affinity and stoichiometry as well as small molecule binding modulation. Additionally, BIND assays allow users to interrogate individual binding events within a multi-component binding reaction. SRU offers a variety of biosensor surface chemistries for maximum flexibility in the type as well as amount of immobilized target.

Application Features
  • Direct Binding, Label-free Assays
  • Rapid Assay Development
  • Plug-and-play Chemistry
  • Low to Ultra-high Throughput Formats
  • Affinity, Specificity & Stoichiometry Determination
Direct Binding Assay Flexibility
BIND technology can be used to probe binding of a variety of targets including proteins, peptides, nucleic acids and small molecules. This flexibility in combination with the variety of biosensor immobilization chemistries provides researchers the freedom to develop binding assays using multiple configurations.

Nuclear Receptor – Cofactor Binding Assay

Figure 1 – A). Nuclear receptor (NR) was immobilized on BIND biosensor surface followed by addition of saturating amounts of small molecules. Small molecule binding was measured followed by addition of peptide cofactor and its binding monitored. Peptide only was added to wells coated with a low and high density of NR. B). BIND Biosensors were coated with NR followed by addition of cofactor peptide. After monitoring cofactor binding, small molecules were added and binding assessed. C). Biotinylated cofactor peptide was immobilized on Streptavidin-coated BIND Biosensors (SA1). Test compounds were added first, followed by the addition of the nuclear receptor. Data courtesy of GSK.
Nuclear receptors (NR) are of high interest as therapeutic targets. BIND was used to create binding assay between a nuclear receptor and its cofactor for use screening a small molecule library for binding modulators. The assays was successfully developed using 3 different configurations. All configurations used a 25kDa nuclear receptor and 3000Da cofactor peptide as well as 400Da small molecule agonist and antagonist. Figure 1 displays the configuration denoting the immobilized target, order of addition and BIND results. Binding of individual components including small molecules was clearly evident. Small molecules that enhanced or inhibited cofactor binding could be identified. Cofactor peptide alone was added to two different BIND biosensors which had different densities of NR immobilized (Figure 1A). Those biosensors with a high density of NR showed high binding of peptide as anticipated. The first 2 assay configurations focus on changing the order of addition which provides information on the mechanism of action.