| abstract |
The present invention relates to a method and a device for determining a concentration of a biological active substance in a sample by the means of an enzyme-linked immunosorbent assay (ELISA). The device comprises a solid support within a tubing ( 17 ) for binding an immunosorbent and an inlet ( 18, 19 ) for fluids, a detector ( 15 ) for detecting radiation due to an activity in said tubing ( 17 ), wherein said tubing ( 17 ) is arranged inside a microchip ( 10 ) extending substantially in one plane, for conducting the fluids along the plane of the microchip ( 10 ). Said tubing ( 17 ) forms a reaction cell having a large detection area ( 22 ). The reaction cell of the microchip ( 10 ) is arranged perpendicular to the detector ( 15 ). n The method comprises the steps of introducing the fluids into the tubing ( 17 ), conducting the fluids through the tubing ( 17 ) forming a reaction cell, in which reaction cell the radiation emitting activity takes place, and detecting the light emitted from the reaction cell substantially perpendicular to the plane. |