Method for coating a substrate quickly and uniformly with a small volume of fluid

• US 6,406,851 B1
• Filed: 01/28/2000
• Issued: 06/18/2002
• Est. Priority Date: 01/28/2000
• Status: Expired due to Fees

• Current Assignee: Agilent Technologies Europe BV (Agilent Technologies, Inc.)
• Original Assignee: Agilent Technologies, Inc.
• Inventors: Bass, Jay K.
• Primary Examiner(s): Naff, David M.
• Application Number:
  US09/494,187
• Time in Patent Office: 872 Days
• Field of Search: 435/174, 435/177, 435/6, 435/89, 530/402, 530/810, 530/812
• US Class Current: 435/6.14
• CPC Class Codes: B01J 2219/00351 Means for dispensing and evacuation of reagents
• CPC Class Codes: B01J 2219/0036 Nozzles
• CPC Class Codes: B01J 2219/00418 using pressure
• CPC Class Codes: B01L 3/0293 for liquids
• CPC Class Codes: B05D 1/26 performed by applying the liquid or other fluent material from an outlet device in contact with, or almost in contact with, the surface
• CPC Class Codes: C07K 17/00 Carrier-bound or immobilised peptides carrier-bound or immobilised enzymes C12N11/00; Preparation thereof
• CPC Class Codes: C40B 60/14 for creating libraries
• CPC Class Codes: Y10S 530/81 Carrier - bound or immobilized peptides or proteins and the preparation thereof, e.g. biological cell or cell fragment as carrier
• CPC Class Codes: Y10S 530/812 Peptides or proteins is immobilized on, or in, an organic carrier

Abstract

A method is provided for applying a small volume of fluid such as fluids used in DNA array fabrication quickly and uniformly onto a surface of a solid substrate. The method employs a distribution member having an upper surface and a lower surface, and including a permeable portion having channels therethough. The distribution member is positioned such that the lower surface of the distribution member is in opposing relation to the surface of the substrate and separated therefrom such as with a spacer to define an application volume between the lower surface of the distribution member and the substrate surface. Once the distribution member is in position, a volume of the fluid is dispensed onto the upper surface of the permeable portion of the distribution member such that the fluid penetrates the distribution member and is retained thereby. In addition, a distribution pressure differential is applied between the upper and lower surfaces without using mechanical means such as a squeegee so that a portion of the fluid passes through the channels of the permeable portion of the distribution member and onto the solid substrate surface. The volume of fluid dispensed is preferably no more than about 150% of the application volume. A biomolecule such as a polynucleotide or polypeptide may be in the fluid or covalently attached to the substrate surface. Other embodiments include an apparatus for carrying out the aforementioned method and a reagent application station for applying a plurality of reagents onto a surface of a solid substrate.

Claims

1. A method for applying a fluid onto a surface of a solid substrate, said method comprising:

(a) positioning a distribution member, said distribution member having an upper surface and a lower surface and including a permeable portion having channels therethrough, such that the lower surface of the distribution member is in opposing relation to the surface of the substrate and separated therefrom by a spacer thereby defining an application volume between the lower surface of the distribution member and the substrate surface;

(b) dispensing a fluid volume of the fluid onto the upper surface of the permeable portion of the distribution member such that the fluid penetrates and is retained by the permeable portion of the distribution member wherein said fluid volume does not substantially exceed said application volume; and

(c) applying a distribution pressure differential between the upper and lower surfaces without using a squeegee such that a portion of the fluid passes through the channels of the permeable portion of the distribution member and onto the solid substrate surface.

2. The method of claim 1, wherein step (b) comprises applying a pressure differential between the upper and lower surfaces of the distribution member wherein said pressure differential is sufficient to effect loading of fluid into the permeable portion of the distribution member.

3. The method of claim 1, wherein step (a) further comprises positioning the distribution member in generally uniformly spaced relation to the substrate surface.

4. The method of claim 1, wherein step (c) comprises raising pressure at the upper surface of the distribution member.

5. The method of claim 1, wherein step (c) comprises lowering pressure at the lower surface of the distribution member.

6. The method of claim 1, further comprising:

(d) flushing a second fluid through the permeable portion of the distribution member such that a portion of the fluid is displaced away from the solid substrate surface.

7. The method of claim 1, further comprising:

(d) flushing a gas through the permeable portion of the distribution member such that a portion of the fluid is displaced away from the solid substrate surface.

8. The method of claim 7, wherein the gas comprises nitrogen or argon.

9. The method of claim 1, wherein the fluid comprises water, acetonitrile, an alcohol, an acid, a base, an oxidizing agent, a reducing agent, or a ketone.

10. The method of claim 1, wherein the fluid contains a biomolecule.

11. The method of claim 10, wherein the biomolecule is an oligonucleotide, polynucleotide, oligopeptide, or polypeptide.

12. The method of claim 1, wherein the fluid volume is no more than about 150% of the application volume.

13. The method of claim 1, wherein the fluid volume of the fluid is no more than about 110% of the application volume.

14. The method of claim 1, wherein the distribution member is generally planar.

15. The method of claim 1, wherein the distribution member is substantially flat and perforated.

16. The method of claim 1, wherein the distribution member comprises a mesh.

17. A method for applying a fluid onto a surface of a solid substrate having a biomolecule attached thereto, said method comprising:

(a) positioning a distribution member, said distribution member having an upper surface and a lower surface and including a permeable portion having channels therethrough, such that the lower surface of the distribution member is in opposing relation to the surface of the substrate and separated therefrom by a spacer thereby defining an application volume between the lower surface of the distribution member and the substrate surface;

(b) dispensing the fluid onto the upper surface of the permeable portion of the distribution member such that the fluid penetrates and is retained by the permeable portion of the distribution member wherein said fluid volume does not substantially exceed said application volume; and

(c) applying a distribution pressure differential between the upper and lower surfaces such that a portion of the fluid passes through the channels of the permeable portion of the distribution member and onto the solid substrate surface to contact with the biomolecules.

18. The method of claim 17, wherein the biomolecule is covalently attached to the substrate surface.

19. The method of claim 17, wherein the biomolecule represents a feature in an array attached to the substrate surface.

20. The method of claim 17, wherein the biomolecule is a nucleotidic biomolecule or a peptidic biomolecule.