Chemical Tolerance of Advanced Protein Assays
The Advanced Protein Assays are powerful reagents in that they are very tolerant to many laboratory chemicals that can often interefere with other types of protein assays.
Below is a list of chemicals that have been tested and the concentrations that (1) does not change background readings in the assay and (2) that does not change the color response to protein. In cases where the user measures protein concentrations in a solution where one or more components are above the limit of parameter (2), it becomes important to perform a protein standard curve in the same solution/buffer that the protein samples are in. An example of this is measuring protein concentrations in SDS-PAGE sample buffer as shown in Figure 2 on the ADV01 page.
| Table 1. Chemical tolerance for the ADV01 and ADV02 protein assay reagents | |||||
ADV01 | ADV02 | ||||
| Chemical group | Chemical name | Tested concentration that does not alter protein assay color* | Tested concentration that does not alter response to protein* | Tested concentration that does not alter protein assay color* | Tested concentration that does not alter response to protein* |
| Buffers | Tris pH 8.0 | >1.0 M | >1.0 M | >1.0 M | >1.0 M |
| Hepes pH 8.0 | >1.0 M | >1.0 M | >1.0 M | >1.0 M | |
| Pipes pH 7.0 | >1.0 M | >1.0 M | >1.0 M | >1.0 M | |
| Potassium phosphate pH7.0 | >1.0 M | >1.0 M | >1.0 M | >1.0 M | |
| Sodium bicarbonate pH9.5 | >1.0 M | >1.0 M | >1.0 M | >1.0 M | |
| Reducing agents | BME | >1.0 M | >1.0 M | >1.0 M | >1.0 M |
| DTT | >1.0 M | >1.0 M | >1.0 M | >1.0 M | |
| monothioglycerol | >1.0 M | >1.0 M | >1.0 M | >1.0 M | |
| Denaturants | 8M urea | 100% | 100% | 100% | 100% |
| 5M guanidine-HCl | 100% | 100% | 100% | 100% | |
| Divalent cations | MgCl2 | >1.0 M | >1.0 M | >1.0 M | >1.0 M |
| CaCl2 | >1.0 M | >1.0 M | >1.0 M | >1.0 M | |
| NiCl2 | >1.0 M | >1.0 M | >0.1 M | >0.1 M | |
| Chelating agents | EDTA | >1.0 M | >1.0 M | >1.0 M | >1.0 M |
| EGTA | >1.0 M | >1.0 M | >1.0 M | >1.0 M | |
| Detergents | SDS | 5.00% | 0.50% | 0.10% | 0.10% |
| NP40 | 0.50% | 0.20% | 10% | 1.0% | |
| Triton X-100 | 0.20% | 0.20% | 10% | 0.50% | |
| Tween 20 | 1.00% | 0.50% | 10% | 1.0% | |
| CHAPS | 0.50% | 0.10% | 1.0% | 0.1% | |
| Ampholytes | 0.50% | 0.10% | 1.0% | 0.1% | |
| Solvents | DMSO | 100% | 100% | 100% | 100% |
| DMF | 100% | 100% | 100% | 100% | |
| Ethanol | 100% | 100% | 100% | 100% | |
| Methanol | 100% | 100% | 100% | 100% | |
| Antifoaming agent | Antifoam-C | 30% | 30% | 10% | 10% |
| Acids | Hydrochloric acid | >1.0 M | >1.0 M | >1.0 M | >0.75 M |
| Perchloric acid | >1.0 M | >1.0 M | >1.0 M | >0.75 M | |
| Trichloric acid | >1.0 M | >1.0 M | >1.0 M | >0.50 M | |
| Nitric acid | >1.0 M | >1.0 M | >1.0 M | >0.75 M | |
| Sulfuric acid | >1.0 M | >1.0 M | >1.0 M | >0.25 M | |
| *using 10 µl protein solution in 1.0 ml protein assay reagent | |||||