Systems and methods for detection and quantification of analytes
Devices, systems, and methods for detecting molecules of interest within a collected sample are described herein. In certain embodiments, self-contained sample analysis systems are disclosed, which include a reusable reader component, a disposable cartridge component, and a disposable sample collection component. In some embodiments, the reader component communicates with a remote computing device for the digital transmission of test protocols and test results. In various disclosed embodiments, the systems, components, and methods are configured to identify the presence, absence, and/or quantity of particular nucleic acids, proteins, or other analytes of interest, for example, in order to test for the presence of one or more pathogens or contaminants in a sample.
1. A method of actuating fluid flow within a microfluidic cartridge, the method comprising:
mixing a sample and reagents in fluid within a fluid-holding reservoir;
heating a valve comprising a phase-changeable material disposed in an outlet to the fluid-holding reservoir using a heater positioned adjacent to the outlet, wherein heating the valve comprises melting the phase-changeable material such that the phase-changeable material does not occlude the outlet;
after melting the phase-changeable material, flowing the fluid comprising the sample and the reagents mixed therein from the fluid-holding reservoir through the outlet and into a microfluidic channel; and
sensing at least one of a presence, absence, or quantity of one or more analytes within the sample,
wherein the fluid-holding reservoir, the microfluidic channel, the valve, and the heater are enclosed in a microfluidic cartridge housing.
2. The method of claim 1 , wherein the phase-changeable material is a hydrophilic wax comprising at least one of hexadecanol and octodecanol.
3. The method of claim 2 , wherein an amount of hydrophilic wax is below 1 microliter in a liquid state.
4. The method of claim 1 , further comprising, before mixing the sample and the reagents in the fluid, inserting an end of a sample collection device exposed to the sample in the fluid-holding reservoir.
5. The method of claim 4 , further comprising locking the sample collection device within an input tunnel of the microfluidic cartridge.
6. The method of claim 1 , wherein the heater is a resistive heater.
7. The method of claim 6 , wherein the resistive heater comprises a serpentine trace on a printed circuit board.
8. The method of claim 1 , wherein heating the valve comprises heating a via adjacent the phase-changeable material using the heater to melt the phase-changeable material.
9. The method of claim 8 , wherein the via is positioned in a printed circuit board enclosed within the microfluidic cartridge housing.
10. The method of claim 9 , further comprising electrically coupling electrical leads of the printed circuit board to a reader.
11. The method of claim 1 , wherein mixing the sample and the reagents in the fluid comprises mixing the sample and the reagents in the fluid using a sonicator.
12. The method of claim 11 , wherein the sonicator comprises a piezoelectric disk disposed adjacent the fluid-holding reservoir.
13. The method of claim 1 , wherein the microfluidic cartridge housing comprises two lateral cover components configured to be coupled together to enclose the fluid-holding reservoir, the microfluidic channel, the valve, and the heater.
14. The method of claim 1 , wherein the reagents comprise:
a plurality of magnetic particles having surface-bound affinity molecules;
a plurality of detector agents; and
a plurality of agents to facilitate access to the one or more analytes and binding between the one or more analytes and the surface-bound affinity molecules and the detector agents.
15. The method of claim 1 , wherein the fluid comprising the sample and the reagents comprises a plurality of sandwich complexes formed of the one or more analytes bound to both a surface affinity molecule on a surface of a magnetic particle and a detector agent.
16. The method of claim 15 , wherein sensing comprises sensing at least one of the presence, the absence, or the quantity of the one or more analytes within the sample in a quantity proportional to a quantity of the one or more analytes present within the sample localized at a sensor within the microfluidic channel.
17. The method of claim 15 , further comprising flowing fluid comprising a chemical substrate from a chemical substrate reservoir into the microfluidic channel,
wherein sensing comprises sensing at least one of the presence, the absence, or the quantity of the one or more analytes within the sample based on reactions between the chemical substrate and the one or more detector agents localized at a sensor within the microfluidic channel.
18. The method of claim 17 , before flowing the fluid comprising the chemical substrate from the chemical substrate reservoir, heating a second valve comprising a second phase-changeable material disposed in a second outlet to the chemical substrate reservoir using a second heater positioned adjacent to the second outlet, wherein heating the second valve comprises melting the second phase-changeable material such that the second phase-changeable material does not occlude the second outlet.
19. The method of claim 17 , further comprising flowing fluid comprising a wash solution from a wash reservoir into the microfluidic channel.
20. The method of claim 1 , wherein sensing comprises sensing at least one of the presence, the absence, or the quantity of the one or more analytes within the sample using a sensor disposed at the microfluidic channel to generate a signal,
further comprising transmitting the signal to a reader electrically coupled to the microfluidic cartridge; and
processing the signal using the reader to generate a processed signal.
21. The method of claim 20 , further comprising transmitting the processed signal from the reader to a computing device.
22. The method of claim 21 , further comprising displaying information indicative of at least one of the presence, the absence, or the quantity of the one or more analytes within the sample using the computing device based on the processed signal.
23. The method of claim 1 , further comprising electrically coupling the microfluidic cartridge to a reader comprising a processor,
wherein heating the valve comprises heating the valve responsive to the processor executing instructions stored in a memory.