This high-affinity streptavidin (SA) sensor chip immobilizes biotinylated molecules for surface plasmon resonance (SPR) interaction analysis on Biacore systems. Versatile: immobilizes biotinylated peptides, proteins, nucleic acids, or carbohydrates Ready-to-use: streptavidin is pre-immobilized, ready for fast, high-affinity ligand capture Robust: streptavidin-biotin is one of the strongest non-covalent interactions in nature Non-covalent: a convenient alternative for ligands refractory to covalent immobilization Standardized ligand orientation: controlled biotinylation enables oriented capture Streptavidin-biotin capture Sensor Chip SA provides a surface of streptavidin covalently attached to a carboxymethyldextran matrix. Dissociation of biotinylated ligands from the surface of the chip is generally negligible during the course of a Biacore analysis because the affinity of streptavidin for biotin is extremely high, with an equilibrium dissociation constant of about 10-15 M. High binding capacity, reproducibility, and chemical resistance give excellent performance over a broad range of applications. The surface of Sensor Chip SA is resistant to 1-minute pulses of many agents commonly used in SPR sensor chip washing and regeneration protocols (Table 1). Agent Concentration Acetonitrile 30% DMSO 10% DTE 0.1 M EDTA 0.35 M Ethanol 70% Ethanolamine 1 M Ethynel glycol 100% Formamide 40% Formic acid 20% Glycine pH 1.5 to 3.0 100 mM HCI 100 mM Imidazole 300 mM MgCI2 4 M NaOH 100 mM NaCI 5 M SDS 0.5% Surfactant P20 5% Urea 8 M Table 1. Common agents compatible with Sensor Chip SA (see also Instruction 22-0564-88 AD) Biacore Sensor Chip SA applications Biotin has become a popular molecular tag for capture and interaction studies because it is stable and rarely interferes with target activity or structure due to its small size. Biotin can be conveniently conjugated to a wide range of target molecules by chemical or enzymatic means. Applications for Sensor Chip SA are therefore broad. Examples include: capture of intact liposomes for protein-membrane interaction studies screening of endocrine-disrupting chemicals elucidating DNA- and RNA- mediated mechanisms of catechins in cancer prevention Sensor chip formats for Biacore systems Biacore sensor chips are available in two formats: “S series” sensor chips are for use with Biacore 8K+, Biacore 8K, Biacore S200, Biacore T200, and Biacore 4000 SPR systems. Sensor chips not designated with “S series” are designed for Biacore X100, Biacore 3000 and Biacore C SPR systems.