Analyte depletion for sensor equilibration
Methods include treating a portion of a sample composition to be tested for presence of an analyte by depleting or blocking the target analyte. The treated composition may be used to equilibrate an acoustic wave sensor prior to exposing the sensor to the untreated sample composition for analysis. By using the treated sample composition, in which the analyte is depleted or blocked, to equilibrate the sensor, the sensor may be equilibrated with a composition having a similar viscosity and non-specific binding characteristics to the untreated sample composition, which should result in improved accuracy when analyzing the analyte in the untreated sample composition.
1. A device for determining the presence of an analyte in a sample composition, the device comprising:
a sample compartment for containing the sample composition to be tested for the presence of an analyte;
an acoustic wave sensor having a surface to which an analyte capture ligand is bound;
a first fluid flow path from the sample compartment to the acoustic wave sensor;
a second fluid flow path from the sample compartment to the acoustic wave sensor;
a material configured to remove the analyte from the sample composition, wherein the material is positioned to contact the sample composition when the sample composition is in the first fluid flow path but does not contact the sample composition when the sample composition is in the second fluid flow path, wherein the material is upstream of the acoustic wave sensor.
2. The device of claim 1 , wherein the sample compartment comprises a first sub-chamber and a second sub-chamber and wherein the first fluid flow path comprises the first sub-chamber and the second fluid flow path comprises the second sub-chamber.
3. The device of claim 2 , wherein the sample compartment is configured to cause a first portion of the sample composition to enter the first sub-chamber and a second portion of the sample composition to enter the second sub-chamber when the sample composition is introduced into the sample compartment.
4. The device of claim 2 , wherein the material configured to remove the analyte from the sample composition is contained in the first sub-chamber.
5. The device of claim 1 , wherein the first fluid flow path comprises a channel, and wherein the material configured to remove the analyte from the sample composition is disposed in or on the channel.
6. The device of claim 1 , wherein the first and second fluid flow paths converge upstream of the acoustic wave sensor.