Assay Report Card

ID: ALA3888508

Type: Binding

Description: Surface Plasmon Resonance (SPR)Assay: The interactions between compounds and ABAD were performed using the dual flow cell BIACORE 3000 instrument. Surface Plasmon Resonance (SPR) studies were performed on a BIACORE 3000 at 25° C. SPR binding experiments with ABAD were performed in phosphate-buffered saline (PBS, pH 7.4, 0.005% surfactant P20) as the running and the sample buffer. The surface of the sensor chip was first activated with mixtures of N-hydroxysuccinimide (NHS, 115 mg/ml) and N-(3-dimethyl-aminopropyl)-N'-ethyl-carbodiimide-hydrochloride (EDC, 750 mg/ml) for 7 minutes. ABAD was dissolved in PBS buffer (pH 5.0) at a concentration of 10 μg/ml. The protein was immobilized directly and covalently on the hydrophilic carboxymethylated dextran matrix of the CM5 sensor chip (BIACORE) by using the standard primary amine coupling reaction on a CM5 sensor chip according to standard procedures. After the immobilization of the protein, excess activated carboxylic acid groups were quenched with ethanolamine (1 M, pH 8.5). Special care was taken during injection of samples because of carryover effects. Special washing routines were used to clean the system before injection of new samples. In addition, predipping of needles was performed. The sample flow was 40 μl/minute in experiments performed for the determination of the kinetic and equilibrium constants. Regeneration of the surfaces between subsequent binding experiments was achieved by washing the surface extensively (>>1 hour) with buffer solution.