Apparatus and method for nanoflow liquid jet and serial femtosecond x-ray protein crystallography
Techniques for nanoflow serial femtosecond x-ray protein crystallography include providing a sample fluid by mixing a plurality of a first target of interest with a carrier fluid and injecting the sample fluid into a vacuum chamber at a rate less than about 4 microliters per minute. In some embodiments, the carrier fluid has a viscosity greater than about 3 centipoise.
1. A method comprising:
providing a sample liquid by flowing a plurality of a first target of interest with a carrier liquid; and
injecting the sample liquid through a capillary tube at a rate of about 4 microliters per minute or less than 4 microliters per minute, without a gas sheath flow, to form a cone or jet at a first position outside the capillary tube,
wherein
the first position is configured to intersect an X-ray beam;
the carrier liquid is electrically conductive; and
injecting the sample liquid further comprises injecting the sample liquid by applying a first voltage to the sample liquid upstream of the first position and a different second voltage to a counter electrode downstream of the first position.
2. A method as recited in claim 1 , wherein injecting the sample liquid further comprises injecting the sample liquid at a rate of about 1 microliter per minute or less than 1 microliter per minute.
3. A method as recited in claim 1 , wherein providing the sample liquid further comprises providing the sample liquid by flowing a plurality of nanoscale crystals of the first target of interest with the carrier fluid.
4. A method as recited in claim 3 , wherein the nanoscale crystals are each about 500 nanometers or smaller than 500 nanometers in a largest dimension.
5. A method as recited in claim 1 , wherein providing the sample liquid further comprises providing the sample liquid by flowing the carrier liquid in a concentric flow around the plurality of the first target of interest.
6. A method as recited in claim 1 , wherein injecting the sample liquid further comprises injecting the sample liquid into a vacuum chamber through a capillary tube that terminates inside the vacuum chamber; the first position is inside the vacuum chamber; and the counter-electrode is disposed inside the vacuum chamber.
7. A method as recited in claim 6 , wherein the viscosity of the carrier liquid is about 3 centipoise or greater than 3 centipoise.
8. A method as recited in claim 1 , wherein the sample liquid in the jet has a diameter about equal to a diameter of the X-ray beam.
9. A method as recited in claim 8 , wherein the sample liquid in the jet has a diameter of about one micrometer or less than one micrometer.
10. A method as recited in claim 6 , wherein the vacuum chamber does not include a shroud to separate the vacuum chamber into two or more volumes pumped to different vacuum pressures.
11. A method as recited in claim 1 , wherein injecting the sample liquid through the capillary tube further comprises injecting the sample liquid through a silicon capillary tube of diameter of about 25 micrometers, or about 95 micrometers or from 25 micrometers to 95 micrometers.
12. A method as recited in claim 1 , wherein:
the X-ray beam is a femtosecond pulse high energy X-ray beam; and
the method further comprises measuring at an X-ray detector array an X-ray scattering pattern for the first target in the sample liquid in response to exposing the cone or jet of the sample liquid to the X-ray beam.
13. A method as recited in claim 1 , wherein the carrier liquid comprises 10% by volume PEG 2000 and 30% sucrose solution with a sucrose concentration of about 1.1 Molar or about 1.4 Molar or in a range from 1.1 Molar to 1.4 Molar.
14. An apparatus comprising:
an inline mixing apparatus configured to produce a sample liquid from a plurality of a target of interest and an electrically conductive carrier fluid;
a capillary tube in fluid communication with the inline mixing apparatus at a first end configured to supply the sample liquid inside the capillary tube, wherein the capillary tube is open at a distal end opposite to the first end;
a voltage source configured to apply a first voltage to the sample liquid inside the capillary tube;
a counter electrode configured to be charged at a different second voltage; and
a source of an X-ray beam configured to intersect a cone or jet of the sample liquid at a first position between the distal end of the capillary tube and the counter electrode,
wherein
a different concentric tube configured to provide a gas sheath flow is omitted.
15. An apparatus comprising:
means for providing a sample liquid by flowing a plurality of a first target of interest with a carrier liquid; and
means for injecting the sample liquid through a capillary tube at a rate of about 4 microliter per minute or less than 4 microliters per minute without a gas sheath flow to form a cone or jet at a first position outside the capillary tube,
wherein
the first position is configured to intersect an X-ray beam;
the carrier liquid is electrically conductive; and
injecting the sample liquid further comprises injecting the sample liquid by applying a first voltage to the sample liquid upstream of the first position and a different second voltage to a counter electrode downstream of the first position.
16. A non-transitory computer-readable medium carrying one or more sequences of instructions, wherein execution of the one or more sequences of instructions by one or more processors causes an apparatus to perform:
applying a first voltage to a sample liquid and a different second voltage to a counter electrode;
injecting the sample liquid through a capillary tube at a rate of about 4 microliters per minute or less than 4 microliters per minute without a gas sheath flow, to form a cone or jet at a first position downstream of the capillary tube and upstream of the counter electrode; and
causing an X-ray source to generate an X-ray beam that intersects the cone or jet at the first position,
wherein the sample liquid comprises a plurality of a target of interest in flow with an electrically conductive carrier fluid.
17. An apparatus as recited in claim 14 , wherein the inline mixing apparatus is a concentric flow apparatus configured to flow the carrier liquid in a concentric flow around the plurality of the first target of interest.
18. An apparatus as recited in claim 15 , wherein the means for providing the sample liquid further comprises means for providing the sample liquid by flowing the carrier liquid in a concentric flow around the plurality of the first target of interest.
19. A non-transitory computer-readable medium as recited in claim 16 , wherein injecting the sample liquid further comprises causing the carrier liquid to flow in a concentric flow around the plurality of the first target of interest.