Patent ID: 7026131

Claim:
A method for determining the presence of antibodies to an ABO blood group of an individual's blood sample by reverse-typing on an optical bio-disc comprising: applying a blood sample to at least one microfluidic channel in the optical bio-disc including a separation chamber with at least one microfilter, at least one mixing chamber, and at least one capture chamber; spinning the optical bio-disc for a first time at a first speed to effect separation of the blood sample into cells and serum in the separation chamber; spinning the optical bio-disc for a second time at a second speed higher than the first, the second speed effecting movement of the serum through the microfluidic channel into a mixing chamber; adding cells of a known ABO blood group cells into the mixing chamber containing serum; spinning the optical bio-disc for a third time in one direction and alternately in another direction at least once to effect mixing of the serum and the cells; incubating the cells in the serum for a sufficient period of time to allow antibody-antigen binding; spinning the optical bio-disc for a fourth time at a third speed higher than the second, the third speed effecting movement of the cells into a capture chamber, the capture chamber including surface with a molecule that binds cells; incubating the sample in the capture chamber to promote cell binding to the capture chamber surface; spinning the disc for a fifth time to remove non-bound cells from the capture chamber; scanning the capture chamber with an incident beam of electromagnetic radiation by rotating the disc about an axis substantially perpendicular to a first face of the disc and by moving the incident beam in a direction radial to the axis; detecting a return beam of electromagnetic radiation formed by at least a part of the incident beam after interacting with the disc; converting the return beam into an output signal; analyzing the output signal to determine the presence of agglutinated cells; and determining the presence of antibodies in the sample.