Thermochromic sensing for nanocalorimetry
A nanocalorimeter device includes a substrate having test cells, each test cell comprising a sample location. Each sample location includes a reaction surface suitable for an enthalpic reaction of constituents of liquid droplets, droplet movement and configured to merge the droplets, and a layer of thermochromic material thermally coupled to the reaction surface. The thermochromic material is configured to exhibit a spectral shift in light emanating from the thermochromic material in response to a change in temperature of the merged droplets.
1. A nanocalorimeter device comprising:
a substrate having test cells, each test cell comprising a sample location comprising:
a reaction surface suitable for an enthalpic reaction of constituents of liquid droplets;
one or more droplet movement features configured to merge the droplets; and
a layer of thermochromic material thermally coupled to the liquid droplets, wherein light emanating from the thermochromic material exhibits a spectral shift in response to a change in temperature of the liquid droplets.
2. The device of claim 1 , wherein each test cell further comprises a reference location comprising a surface suitable to receive reference droplets, the one or more droplet movement features, and the layer of thermochromic material thermally coupled to the reference droplets.
3. The device of claim 1 , wherein the substrate is at least partially transparent to the light emanating from the thermochromic material.
4. The device of claim 1 , wherein the droplet movement features are at least partially transparent to the light emanating from the thermochromic material.
5. The device of claim 1 , wherein the droplet movement features comprise a first electrode and a second electrode spaced apart from the first electrode.
6. The device of claim 1 , wherein the droplet movement features comprise an optically controlled surface structure.
7. The device of claim 1 , wherein at least one of a surface of, a coating on, and a modified surface layer of the thermochromic material comprises the reaction surface.
8. The device of claim 1 , wherein the thermochromic material is disposed between the reaction surface and the droplet movement features.
9. The device of claim 1 , further comprising a hydrophobic layer disposed at least at the reaction surfaces of the sample locations.
10. The device of claim 9 , wherein the hydrophobic layer is at least partially transparent to the light emanating from the thermochromic material.
11. The device of claim 1 , wherein the thermochromic layer is disposed between the droplet movement features and the substrate.
12. The device of claim 1 , wherein the thermochromic layer is on an opposite surface of the substrate from the reaction surface.
13. The device of claim 1 , wherein the droplet movement features of location are disposed within a thermal equilibration region.
14. The device of claim 13 , wherein the thermal equilibration region comprises a thermally conductive component.
15. The device of claim 14 , wherein the thermally conductive component is at least partially transparent to the light emanating from the thermochromic layer.
16. The device of claim 14 , wherein the thermally conductive component is between the thermochromic layer and the substrate.
17. The device of claim 16 , wherein the thermally conductive component is at least partially transparent to the light emanating from the thermochromic layer.
18. The device of claim 1 , further comprising a barrier layer disposed over the substrate and the barrier layer is at least partially transparent to the light emanating from the thermochromic layer.
19. The device of claim 1 , wherein the thermochromic material comprises one or more of thermochromic liquid crystals, leuco dye, a fluorophore, Prodan bound to DPPC, or a fluorescent protein.
20. The device of claim 1 , wherein the light emanating from the thermochromic material is configured to exhibit the spectral shift as a function of temperature in a range of 0.5 nm/K to 1000 nm/K.
21. The device of claim 1 , further comprising a magnetic droplet mixing material disposed at each of the locations, the droplet mixing material configured to mix the droplets after merging.
22. The device of claim 1 , further comprising a surface structure that can be optically altered to mix the droplets after merging.
23. The device of claim 1 , further comprising a cap having at least one cavity that is positioned above and in contact with an upper surface of the device, the cap forming a seal around one or more of the test cells.