Biuret Protein Colorimetric Assay Kit
To better serve you, we would like to discuss your specific requirement, Please Contact Us for a quote.
Biuret Protein Colorimetric Assay Kit
| SKU # | E-BC-K165-S |
| Detection Instrument | Spectrophotometer (540 nm) |
| Detection method | Colorimetric method |
Product Details
Properties
| Synonyms | TP |
| Sample Type | Serum, plasma, tissue |
| Sensitivity | 0.373 g/L |
| Detection Range | 0.373-80 g/L |
| Detection Method | Colorimetric method |
| Assay type | Quantitative |
| Assay time | 50 min |
| Precision | Average inter-assay CV: 2.600% | Average intra-assay CV: 1.200% |
| Other instruments required | Micropipettor, Incubator |
| Other reagents required | Normal saline (0.9% NaCl), PBS (0.01 M, pH 7.4) |
| Storage | Reagent 3: -20℃, others: 2-8℃ |
| Valid period | 12 months |
Dilution of Sample
It is recommended to take 2~3 samples with expected large difference to do pre-experiment before formal experiment and dilute the sample according to the result of the pre-experiment and the detection range (0.373-80 g/L).
The recommended dilution factor for different samples is as follows (for reference only):
| Sample type | Dilution factor |
| Porcine serum | 2-4 |
| Human serum | 2-4 |
| 5% Mouse liver tissue homogenization | 1 |
| 10% Epipremnum aureum tissue homogenization | 1 |
| 5% Mouse heart tissue homogenization | 1 |
Note: The diluent is normal saline (0.9% NaCl) or PBS (0.01 M, pH 7.4).
Detection Principle
Any compound that contains two -CONH2 in the molecule can react with alkaline copper solution to form a purple complex, which is known as the biuret reaction. Many peptide bonds (-CONH-) in protein molecules can perform this reaction, and the color degree of all kinds of proteins are essentially the same.
Kit Components & Storage
| Item | Component | Specification | Storage |
| Reagent 1 | Copper Reagent | Powder × 1 vial | 2-8°C, 12 months |
| Reagent 2 | Alkali | Powder × 1 vial | 2-8°C, 12 months, shading light |
| Reagent 3 | 50 g/L Protein Standard | 1.6 mL ×1 vial | -20°C, 12 months |
Note: The reagents must be stored strictly according to the preservation conditions in the above table. The reagents in different kits cannot be mixed with each other.
Technical Data:
Parameter:
Intra-assay Precision
Three human serum samples were assayed in replicates of 20 to determine precision within an assay. (CV = Coefficient of Variation)
| Parameters | Sample 1 | Sample 2 | Sample 3 |
| Mean (g/L) | 2.50 | 38.50 | 95.00 |
| %CV | 4.2 | 3.4 | 4.4 |
Inter-assay Precision
Three human serum samples were assayed 20 times in duplicate by three operators to determine precision between assays.
| Parameters | Sample 1 | Sample 2 | Sample 3 |
| Mean (g/L) | 2.50 | 38.50 | 95.00 |
| %CV | 6.2 | 7.5 | 5.8 |
Recovery
Take three samples of high concentration, middle concentration and low concentration to test the samples of each concentration for 6 times parallelly to get the average recovery rate of 98%.
| Standard 1 | Standard 2 | Standard 3 | |
| Expected Conc. (g/L) | 15 | 56 | 72 |
| Observed Conc. (g/L) | 15.2 | 52.6 | 71.3 |
| Recovery rate (%) | 101 | 94 | 99 |
Sensitivity
The analytical sensitivity of the assay is 0.58 g/L. This was determined by adding two standard deviations to the mean O.D. obtained when the zero standard was assayed 20 times, and calculating the corresponding concentration.