Patent ID: 8841082

Claim:
A method for quantifying a minor erythrocyte cell population in heterogeneous erythrocyte cell populations or for detecting an analyte which is present at a low concentration on erythrocyte cells, comprising the steps of: a) mixing an amount of a blood sample with a diluent to provide a liquid sample, wherein the concentration of the minor erythrocyte cell population, based on the total heterogeneous erythrocyte cell population, is less than 1% or wherein the analyte is present in less than 30 antigens per erythrocyte cell and wherein the amount of the diluent is lower than or equal to the amount of the blood sample; b) applying approximately from 200 μl to 500 μl of the liquid sample containing cells of step a) to a feeding zone; c) applying the diluent; d) performing an assay comprising incubating the liquid sample of step a) with the test device such that the applied sample migrates from the feeding zone through indicator zones to an absorption region; e) concentrating the minor erythrocyte cell population by binding to the indicator zone and decreasing the amount of further erythrocyte cell populations at this indicator zone; and f) evaluating the assay by determining whether erythrocyte cells are bound to the indicator zone; said method being carried out using a device comprising: at least one feeding zone ( 5 ) for applying the liquid sample containing cells, a porous membrane ( 2 ) that is suitable for being penetrated by cellular components and that includes at least one indicator zone on the membrane, which indicator zone interacts with cellularly bound analyte in the liquid sample and contains at least one binding element against the cellularly bound analyte, and at least one absorption region ( 3 ) on the membrane, which absorbs the liquid sample after the latter has passed the indicator zone, wherein the at least one indicator zone is located between the feeding zone ( 5 ) and the absorption region ( 3 ).