Matrix-assisted laser desorption ionization mass spectrometry substrates having low volume matrix array elements
Provided herein are substrates for matrix-assisted laser-desorption ionization (MALDI) mass spectrometric analysis. Each spot includes 3-hydroxypicolinic acid matrix and no analyte.
1. A substrate for matrix-assisted laser-desorption ionization (MALDI) mass spectrometric analysis, which comprises a surface having an array of spots, wherein each spot:
comprises 3-hydroxypicolinic acid matrix and no analyte, and
has an amount of the matrix resulting from deposition of a reproduced, defined and controlled 0.2 to 20 nanoliter volume of a solution comprising the matrix and an evaporating solvent.
2. The substrate of claim 1 , wherein the substrate comprises a flat surface, a flat surface with pits or a membrane.
3. The substrate of claim 2 , wherein the substrate comprises a membrane.
4. The substrate of claim 1 , wherein the substrate comprises material selected from the group consisting of silica, glass, cellulose, silicon, metal, plastic, polymer and metal-grafted polymer.
5. The substrate of claim 4 , wherein the substrate comprises silicon.
6. The substrate of claim 5 , which is a flat silicon wafer.
7. The substrate of claim 6 , wherein the silicon wafer comprises pits.
8. The substrate of claim 6 , wherein the spots are about 2.25 millimeters apart.
9. The substrate of claim 6 , wherein the spots are about 1.125 millimeters apart.
10. The substrate of claim 6 , wherein the silicon wafer comprises a hydrophilic flat surface.
11. The substrate of claim 4 , wherein the substrate comprises a metal.
12. The substrate of claim 4 , wherein the substrate comprises a plastic.
13. The substrate of claim 1 , wherein the substrate comprises a metal-grafted polymer.
14. The substrate of claim 1 , wherein the substrate is chemically functionalized.
15. The substrate of claim 14 , wherein the substrate is chemically functionalized with beads.
16. The substrate of claim 14 , wherein the substrate is chemically functionalized with a dendritic material.
17. The substrate of claim 1 , wherein the solution consists essentially of the matrix and the evaporating solvent.
18. The substrate of claim 1 , wherein the solution consists of the matrix and the evaporating solvent.
19. The substrate of claim 1 , wherein the evaporating solvent is CH 3 CN.
20. The substrate of claim 1 , wherein each spot is a flat disk.
21. The substrate of claim 1 , wherein the amount of matrix is reproducible from spot to spot.
22. The substrate of claim 1 , wherein each spot consists essentially of matrix.
23. The substrate of claim 1 , wherein each spot consists of matrix.
24. A substrate for matrix-assisted laser-desorption ionization (MALDI) mass spectrometric analysis, which comprises a surface having an array of spots, wherein
each spot comprises 3-hydroxypicolinic acid matrix resulting from the deposition of a reproduced, defined and controlled nanoliter scale volume and no analyte;
the substrate is a flat silicon chip; and
the center of each spot is about 2.25 millimeters or less from the center of an adjacent spot.
25. The substrate of claim 24 , wherein each spot consists essentially of matrix.
26. The substrate of claim 24 , wherein each spot consists of matrix.
27. The substrate of claim 24 , wherein the silicon wafer comprises pits.
28. The substrate of claim 24 , wherein the center of each spot is about 2.25 millimeters from the center of an adjacent spot.
29. The substrate of claim 24 , wherein the center of each spot is about 1.125 millimeters or less from the center of an adjacent spot.
30. The substrate of claim 29 , wherein the center of each spot is about 1.125 millimeters from the center of an adjacent spot.
31. The substrate of claim 29 , wherein the center of each spot is about 0.5 millimeters from the center of an adjacent spot.
32. The substrate of claim 24 , which comprises a hydrophilic flat surface.