Protein detection reagents and methods with dyes and dextrins
The invention provides reagents, methods and kits for detection of proteins and quantitative determination of protein concentration. The reagents comprise a protein-complexing dye, such as a Coomassie dye and one or more dextrins, for the elimination of interference caused by detergents.
1. A method of detecting and/or quantifying protein comprising contacting a protein-containing sample with a solution comprising:
(a) a protein complexing dye; and
(b) one dextrin selected from α-cyclodextrins, γ-cyclodextrins, linear dextrins and derivatives thereof, or two or more dextrins; and
detecting and/or quantifying dye/protein complex formation, wherein the protein is in the presence of a detergent.
2. The method according to claim 1 , wherein the protein is in solution or the protein is provided on a support.
3. The method according to claim 2 , wherein the support is a gel, sol, chromatography plate, filter paper, nitrocellulose membrane or resin.
4. The method according to claim 3 , wherein the support is a polyacrylamide gel or agarose gel and the protein has been subjected to separation using an electric field.
5. The method according to claim 2 , wherein the support comprises a detergent and/or wherein contacting is performed in the presence of a detergent.
6. The method according to claim 1 , wherein detecting and/or quantifying comprises detecting a change in absorption or emission spectra of the dye/protein complex.
7. The method according to claim 6 , wherein detecting and/or quantifying comprises detecting a colour change.
8. The method according to claim 6 , wherein the protein-complexing dye is a Coomassie G-250 dye and absorbance is measured at a wavelength of about 595 nm.
9. The method according to claim 1 , wherein quantifying is performed by measuring absorbance over time.
10. The method according to claim 6 , wherein the absorbance or emission measured is compared with a standard value, standard set of values, or standard curve.
11. The method according to claim 1 , further comprising providing a support comprising protein, prior to the contacting step.
12. A method comprising contacting a protein-containing sample in the presence of a detergent with a protein binding dye, and one dextrin selected from α-cyclodextrins, γ-cyclodextrins, linear dextrins and derivatives thereof; and detecting and/or quantifying dye/protein complex formation, wherein the protein is in the presence of a detergent.
13. A method of detecting and/or quantifying protein comprising contacting a protein-containing sample in the presence of a detergent with a protein binding dye, and two or more dextrins; and detecting and/or quantifying dye/protein complex.
14. The method according to claim 1 , wherein the one dextrin or two or more dextrins are provided as a reagent comprising a protein-complexing dye and one dextrin.
15. The method according to claim 14 , wherein the reagent is a reagent concentrate.
16. The method according to claim 14 , wherein the reagent further comprises an acid with a pKa of 4 or less.
17. The method according to claim 14 , wherein the reagent further comprises a solubilizing agent.
18. The method according to claim 14 , wherein the reagent does not comprise a protein.
19. The method according to claim 14 , wherein the dye is a Coomassie dye.
20. The method according to claim 1 , wherein the one dextrin, or two or more dextrins concentration is in the range of from about 0.01 to about 200 mg/ml.
21. The method according to claim 14 , wherein the reagent further comprises one or more alcohols, and wherein the alcohol concentration is from about 0.1% to about 10% v/v.
22. The method according to claim 13 , wherein the mixture of two or more dextrins is selected from the group consisting of α-cyclodextrins, β-cyclodextrins, γ-cyclodextrins, cycloamylose, linear dextrins and derivatives thereof.
23. The method according to claim 14 , wherein the reagent is provided as a multipart system.
24. A method of detecting and/or quantifying protein comprising contacting a protein-containing sample with a solution comprising:
(a) a protein-complexing dye, wherein the dye is a Coomassie dye; and
two or more dextrins; and
detecting and/or quantifying dye/protein complex formation, wherein the protein is on a support.
25. A method according to claim 24 , wherein the dye is a Coomassie dye.
26. A method according to claim 24 , wherein the support is a gel, sol, chromatography plate, filter paper, nitrocellulose membrane or resin.
27. The method according to claim 26 , wherein the support is a polyacrylamide gel or agarose gel and the protein has been subjected to separation using an electric field.
28. The method according to claim 24 , wherein the support comprises a detergent and/or wherein contacting is performed in the presence of a detergent.
29. A method of detecting and/or quantifying protein comprising contacting a protein-containing sample with a solution comprising:
(a) a protein-complexing dye; and
(b) one dextrin selected from α-cyclodextrins, γ-cyclodextrins, linear dextrins and derivatives thereof; and
detecting and/or quantifying dye/protein complex formation, wherein the protein is on a support.
30. A method according to claim 29 , wherein the dye is a Coomassie dye.
31. The method according to claim 30 , wherein the Coomassie dye is a Coomassie G-250 dye.
32. A method according to claim 29 , wherein the support is a gel, sol, chromatography plate, filter paper, nitrocellulose membrane or resin.
33. The method according to claim 32 , wherein the support is a polyacrylamide gel or agarose gel and the protein has been subjected to separation using an electric field.
34. The method according to claim 29 , wherein the support comprises a detergent and/or wherein contacting is performed in the presence of a detergent.