COMATIC^® PROTEIN S - FREE

Automated latex ligand immunoassay for the quantitative determination of free Protein S (PS) in human citrated plasma on automated instruments. Two forms of Protein S are present in plasma: free Protein S (40%), and Protein S linked to the complement C4b-binding protein (C4BP) (60%). Only free Protein S has functional cofactor activity.

Measurement Principle

The presence of free Protein S in the sample is measured as the increase of turbidity produced by the agglutination of two latex reagents. Purified C4BP adsorbed onto the first latex reagent reacts with a high affinity for free Protein S of patient plasma in the presence of Ca 2+ ions. The free Protein S adsorbed on the C4BP latex triggers the agglutination reaction with the second latex reagent, which is sensitized with a monoclonal antibody directed against human Protein S. The degree of agglutination will be directly proportional to the free Protein S concentration in the test sample and is determined by measuring the decrease of the transmitted light at 405 nm caused by the aggregates.

Reagents and their stability when opened

Determinations

Part Number: 82 4003 63