Heparin-binding small molecule discovery via fluorescence polarization high-throughput screening assay

Overview

This offering provides access to a validated fluorescence polarization (FA) high-throughput screening (HTS) assay designed to discover small molecule binders of heparin. Heparin is a widely used anticoagulant, and identifying novel binders has applications in anticoagulant therapy development, drug delivery, diagnostic biosensors, and antiviral research. The screening campaign leverages a fluorescein-labeled tetrapeptide probe combined with curated libraries of short peptides, peptididomimetics, and small molecules to identify hit compounds with confirmed heparin affinity.

Technical specifications

Assay platform:

• Fluorescence polarization high-throughput screen run in 384-well plate format
• Probe: FITC-labeled tetrapeptide (FITC-CKGK) carrying two positively charged lysine residues for heparin binding
• Screening executed in duplicate to ensure statistical reliability

Hit-to-lead workflow:

• Initial hit identification from compound library screening
• Computationally guided structure-activity relationship (SAR) studies for lead optimization
• Dose-response confirmation under identical FA assay conditions
• Orthogonal validation using isothermal titration calorimetry (ITC) to determine binding affinity and dissociation constants
• Molecular dynamics simulations (400 ns) supporting binding mode analysis of candidate peptides and small molecules

Team expertise:

• Ligand synthesis, computational chemistry, and biochemistry integrated into a single discovery pipeline
• Access to diverse compound libraries including peptides, peptididomimetics, and small molecules

Technology readiness level

The assay is at an early-to-mid development stage. The FA-based HTS assay is being developed and validated using a known heparin-binding tetrapeptide probe. Preliminary molecular dynamics simulations suggest stable complex formation between heparan sulfate segments and candidate ATH peptides through salt bridges and hydrogen bonds, supporting feasibility. The next steps include full assay validation, library screening, SAR-driven lead optimization, and ITC-based binding affinity confirmation. The platform is positioned for collaborative partnerships to advance identified hits toward specific therapeutic or diagnostic applications.