Stable support films for electron microscopy
View Patent ↗This disclosure provides systems, methods, and apparatus related to arrangements including electron microscopy grids. In one aspect an arrangement includes an electron microscopy grid. The electron microscopy grid comprises a first surface and a second surface, with the first surface having a holey carbon film disposed thereon. A plurality of lipid molecules are disposed in a hole in the holey carbon film. Each lipid molecule of the plurality of lipid molecules has a hydrophilic head and a hydrophobic tail. A biotin-binding protein is attached to the hydrophilic heads of the plurality of lipid molecules. The biotin-binding protein is crystalline.
1. An arrangement comprising:
an electron microscopy grid, the electron microscopy grid comprising a first surface and a second surface, the first surface having a holey carbon film disposed thereon;
a plurality of lipid molecules disposed in a hole in the holey carbon film, the hole in the holey carbon film having a dimension of about 1 micron to 2 microns, each lipid molecule of the plurality of lipid molecules having a hydrophilic head and a hydrophobic tail;
a biotin-binding protein attached to hydrophilic heads of the plurality of lipid molecules, the biotin-binding protein being crystalline, a crystal of the biotin-binding protein spanning the hole in the holey carbon film; and
small molecules disposed on the biotin-binding protein, the small molecules operable to preserve a structure of the biotin-binding protein at room temperature.
2. The arrangement of claim 1 , wherein the small molecules form a layer, and wherein the layer is about 50 nanometers to 150 nanometers thick.
3. The arrangement of claim 1 , further comprising:
a layer of carbon disposed on hydrophobic tails of the plurality of lipid molecules.
4. The arrangement of claim 3 , wherein the layer of carbon has a thickness of 5 nanometers or less.
5. The arrangement of claim 1 , wherein the plurality of lipid molecules comprises a homogenous mixture of lipid molecules with biotinylated head groups.
6. The arrangement of claim 1 , wherein the plurality of lipid molecules comprises a heterogeneous mixture of lipid molecules, and wherein at least a part of the heterogeneous mixture comprises lipid molecules with biotinylated head groups.
7. The arrangement of claim 1 , wherein the biotin-binding protein comprises streptavidin.
8. The arrangement of claim 1 , wherein the small molecules are selected from a group consisting of trehalose, glucose, betaine, proline, and glycine.
9. The arrangement of claim 1 , wherein the holey carbon film is about 10 nanometers to 25 nanometers thick.
10. A method comprising:
(a) providing an electron microscopy grid, the electron microscopy grid comprising a first surface and a second surface, the first surface having a holey carbon film disposed thereon;
(b) providing a plurality of lipid molecules, each lipid molecule of the plurality of lipid molecules having a hydrophilic head and a hydrophobic tail;
(c) contacting the holey carbon film with hydrophobic tails of the plurality of lipid molecules to form a lipid monolayer disposed in a hole in the holey carbon film, the lipid monolayer comprising a portion of the plurality of lipid molecules;
(d) after operation (c), attaching a biotin-binding protein to hydrophilic heads of the lipid monolayer; and
(e) after operation (d), allowing a period of time to elapse to allow the biotin-binding protein to crystalize while being attached to the hydrophilic heads of the lipid monolayer disposed in the hole in the holey carbon film.
11. The method of claim 10 , further comprising:
depositing small molecules on the biotin-binding protein after operation (e).
12. The method of claim 10 , further comprising:
depositing a layer of carbon on the hydrophobic tails of the lipid monolayer.
13. The method of claim 10 , further comprising:
removing the biotin-binding protein that is not attached to the hydrophilic heads of the lipid monolayer after operation (d).
14. The method of claim 10 , wherein the period of time in operation (e) is about 1 minute to 20 minutes.
15. The method of claim 10 , wherein the plurality of lipid molecules comprises a homogenous mixture of lipid molecules with biotinylated head groups.
16. The method of claim 10 , wherein the plurality of lipid molecules comprises a heterogeneous mixture of lipid molecules, and wherein at least part of the heterogeneous mixture comprises lipid molecules with biotinylated head groups.
17. The method of claim 10 , wherein the biotin-binding protein comprises streptavidin.
18. The method of claim 11 , wherein the small molecules are selected a group consisting of trehalose, glucose, betaine, proline, and glycine.
19. The method of claim 10 , wherein the holey carbon film is about 10 nanometers to 25 nanometers thick, and wherein the hole in the holey carbon film has dimensions of about 1 micron to 2 microns.
20. The arrangement of claim 1 , wherein the hole in the holey carbon film has dimensions of about 2 microns.
21. The method of claim 11 , wherein the small molecules form a layer, and wherein the layer is about 50 nanometers to 150 nanometers thick.