Abstract: An aggregometer which is economical and accurate is provided. The aggregometer includes a disposable test cell having two electrode tips. Adjacent parallel planar surfaces of the electrode tips define a channel which is substantially parallel to a flow direction of the sample prior to entering the channel. Also provided is a method for analyzing platelet aggregation by measuring electrical impedance in a sample using the aggregometer.

Abstract: A disposable low cost electrode structure for measuring platelet aggregation in whole blood or PRP which utilizes conductive ink or foil for the electrodes with the electrode pattern printed, heat-stamped or silk-screened onto a suitable plastic non-reactive base. The base material can be any material which does not react with blood and is stiff enough, for example a polycarbonate, while the conductive element can be made with a silver conductive ink. The electrodes can be on one or both sides of the base or substrate material. Platelet aggregates start and build up on the leading edge of a narrow body inserted into the flow path of the blood. The conductive pattern must have its active element on or very near the leading edge of the electrode base material, and in contact with the blood, and the non-active areas of the conductive pattern must be insulated electrically from the blood or plasma being tested so as to allow sensing of the change in resistance caused by the platelet build-up on the active area.