System and method for detecting multiple molecules in one assay

A method for performing an assay on a sample, the method comprising:

• providing a cartridge, which cartridge includes
• a planar waveguide having a plurality of capture molecules bound to a planar surface thereof,
• a refractive volume for optically coupling a light beam provided by a light source to the planar waveguide, the refractive volume being integrally formed from the planar waveguide, and
• a sample chamber for receiving and containing the sample such that the sample comes into contact with the plurality of capture molecules;
• introducing the sample into the sample chamber of the cartridge;
• providing a reader instrument, which reader instrument includes
• a receiving mechanism for positioning the cartridge therein,
• the light source for providing the light beam,
• a detector for detecting a light signal from a portion of the planar surface on which the plurality of capture molecules is bound, and
• an analysis module for receiving and analyzing the light signal from the detector;
• inserting the cartridge, containing the sample, into the reader instrument;
• using the light source, illuminating a portion of the planar waveguide at which the plurality of capture molecules are bound such that, if the sample includes a target analyte, the target analyte interacts with the plurality of capture molecules so as to produce a light signal;
• capturing the light signal;
• and
• analyzing the light signal,
• wherein illuminating includes
• directing the light beam at the refractive volume such that the light beam is incident on the refractive volume in a plane parallel to and offset from the planar waveguide, and
• refracting the light beam such that the light beam is focused at the planar surface at a non-zero, internal propagation angle relative to the planar surface for all light within the light beam.

A kit for performing a biochemical assay on a sample, the kit comprising:

• a cartridge including
• a planar waveguide having a plurality of capture molecules bound to a planar surface thereof,
• a refractive volume for optically coupling a light beam provided by a light source to the planar waveguide, the refractive volume being integrally formed from the planar waveguide, and
• a sample chamber for receiving and containing the sample such that the sample comes into contact with the plurality of capture molecules;
• a reader instrument including:
• a receiving mechanism for positioning the cartridge therein,
• the light source for providing the light beam,
• a detector for detecting a light signal from a portion of the planar surface on which the plurality of capture molecules is bound, and
• an analysis module for receiving and analyzing the light signal from the detector;
• and
• one or more processing solutions,
• wherein the cartridge and the reader instrument cooperate such that the light beam is incident on the refractive volume in a plane parallel to and offset from the planar waveguide, and the light beam is focused at the planar surface at a non-zero, internal propagation angle relative to the planar surface for all light within the light beam, while illuminating a portion of the planar waveguide including the plurality of capture molecules thereby, if the sample includes a target analyte, the target analyte interacts with the plurality of capture molecules so as to produce the light signal capturable by the detector.