Multiple hybrid immunoassay
The invention relates to compositions and methods for the immunoassay of an analyte of interest. The analyte is detected in an immunoassay using three or more antibodies, where in each antibody specifically binds to a different epitope on the analyte. When the analyte of interest in a clinical marker for an acute disease, the detection of the analyte by immunoassay is a diagnosis of the occurrence of the disease.
1. A cartridge for sensing at least one analyte in a sample, said cartridge comprising:
a housing;
at least one sensor located within the housing;
a cavity within the housing including a sealed deformable pouch for retaining an aqueous reagent out of contact with the sensor;
an aqueous reagent conduit for connecting the cavity to the sensor;
aqueous reagent displacer under control of a reading apparatus for displacing the aqueous reagent from the cavity through the aqueous reagent conduit to the sensor;
sample holding chamber within the housing, for retaining the sample out of contact with the sensor, prior to sensing;
sample collector within the housing including an orifice for drawing the sample into the sample holding chamber;
a sample conduit connecting the sample holding chamber with the sensor;
sample displacer for forcibly displacing the sample from said sample holding chamber through the sample conduit and into contact with the sensor to permit sensing; and
an immunoassay composition for detecting said analyte comprising at least three different antibodies, the at least three different antibodies being capable of binding to at least three different epitopes on said analyte, in which at least two of the at least three different antibodies are capable of binding to at least two different epitopes on a subform of said analyte, and in which at least one of the at least three different epitopes on said analyte is unavailable for binding on the subform.
2. The cartridge of claim 1 , wherein said analyte is human cTnI and wherein the sample is a whole blood sample.
3. The cartridge of claim 1 , wherein said at least three different antibodies comprise:
(a) G129C antibody;
(b) G130C antibody; and
(c) at least one additional troponin I antibody different from (a) and (b).
4. The cartridge of claim 2 , wherein (c) is selected from the group consisting of 19C7, A34720, 8E10, A34500, A34440, A34730, and 34503228P.