Afinion^™ AS100 Analyzer – a Multi-Assay System Including a New PT-INR Test

Abstract number: P0704

Brynildsrud T, Janson T

Afinion^™ is a new multi-assay analyzer system for Point-of-Care testing. Available tests are HbA1c and CRP, and a PT-INR test is recently introduced. The PT-INR test is a plain PT test based on Recombinant Rabbit Brain Thromboplastin. Capillary blood, citrated venous blood and plasma can be used as test material. The Afinion^™ PT Test Cartridge contains reagents for one single PT-INR test. The Analyzer uses only 15 µL of blood from a finger prick or a sample tube, collected with a sampling device fitting into the Afinion^™ Test Cartridge. The Cartridge is loaded into the Analyzer, which is operated via a touch screen. The bar code printed on the Cartridge contains three sets of batch specific values to be used in the calculation of the INR result: one set consists of an ISI and normal value for capillary blood, and the two others are for citrated venous blood and plasma, respectively. The values obtained are based on standardization according to WHO guidelines, using both blood and plasma samples. RBT-90 is used as Reference Thromboplastin. The coagulation detection is based on an opto-imechanical principle. A multiwell in the Test Cartridge contains dried Thromboplastin reagent and a steel ball. During the assay, a magnet keeps the steel ball in position as the Cartridge is moved back and forth. When adding 15 µL of blood or plasma, the dried Thromboplastin reagent is dissolved and the reaction is started. When the coagulation end-point is reached, the steel ball is brought out of position and a digital camera records this endpoint. A software program finds the clotting time and the INR result is calculated, based on the batch specific ISI – and normal value given. A unique built-in fail-safe system is monitoring the process.