Sensor incorporating a quantum dot as a reference
First Claim
1. A device for detecting the presence of analyte in a sample, comprising:
- (a) a binding substrate that has at least one affinity binding site for the analyte and a labeled analogue;
(b) said labeled analogue comprising an analogue and a label, wherein the label emits light at a first wavelength when irradiated;
(c) a dye bound to the binding substrate, which has an absorption spectrum that overlaps a fluorescence excitation and emission spectra of the label;
(d) a first reference comprising quantum dots that emit light at a second wavelength when irradiated;
(e) an analyte-permeable membrane that encapsulates components (a), (b), (c), and (d); and
(f) a void volume exterior to the binding substrate and interior to the analyte-permeable membrane.
8 Assignments
0 Petitions
Accused Products
Abstract
The present invention provides a device and methods for quantitatively detecting the presence of an analyte by referencing the analyte variant signal to an analyte invariant reference signal. The devices contain quantum dots as the invariant references. The reference quantum dots provide a fluorescent signal whose intensity in invariant with respect to the optical signal associated with the analyte concentration. Both the optical path for the analyte specific and invariant reference signal are substantially identical. Therefore, by measuring the intensity ratio of the analyte specific signal to the reference signal, errors associated with optical path length, absorptivity and scattering are eliminated.
-
Citations
30 Claims
-
1. A device for detecting the presence of analyte in a sample, comprising:
-
(a) a binding substrate that has at least one affinity binding site for the analyte and a labeled analogue;
(b) said labeled analogue comprising an analogue and a label, wherein the label emits light at a first wavelength when irradiated;
(c) a dye bound to the binding substrate, which has an absorption spectrum that overlaps a fluorescence excitation and emission spectra of the label;
(d) a first reference comprising quantum dots that emit light at a second wavelength when irradiated;
(e) an analyte-permeable membrane that encapsulates components (a), (b), (c), and (d); and
(f) a void volume exterior to the binding substrate and interior to the analyte-permeable membrane. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30)
(a) contacting a sample with the device of claim 1, (b) irradiating the device with light, (c) determining the intensity of emission from the labeled analogue, (d) determining the intensity of emission from the quantum dot reference, (e) correlating the intensity of emission from (c) and (d) to thereby determine the amount of analyte in the sample.
-
-
30. A method of optimizing the signal to noise ratio of an optical sensor, which comprises the steps of:
-
(a) contacting a sample with the device of claim 1, (b) irradiating the device with light, (c) maximizing the labeled analogue signal/noise ratio by optimizing the reference signal intensity by physically moving the excitation source and detector relative to the sensing device.
-
Specification