BCA Protein Assay
Product key features
- Rapid results: Completes assay in 30-60 minutes at room temperature.
- Accurate quantitation: Uses proven copper-chelation chemistry.
- Efficient format: Supports simultaneous analysis of multiple samples in a 96-well format.
- Versatile applications: Suitable for protein quantitation in cell lysates, serum, and other biological fluids.
Product description
Amplite® Colorimetric BCA Protein Quantitation Assay Kit is a colorimetric assay for quantifying total protein concentration in biological samples. It is based on the reduction of Cu²⁺ to Cu⁺ by peptide bonds under alkaline conditions, followed by the chelation of Cu⁺ with bicinchoninic acid (BCA) to form a stable purple complex. The intensity of the color, measured at 562 nm, is directly proportional to protein concentration.
This two-step reaction provides a robust and detergent-compatible assay format. The BCA assay offers a broader detection range and greater stability than traditional Bradford assays, with less variability due to differences in amino acid composition. It is ideal for quantifying proteins in lysates, extracts, or purified preparations, and can be read using a standard microplate reader or spectrophotometer.
Example protocol
AT A GLANCE
- Prepare BCA working solution (50 µL)
- Add BSA standards or test samples (50 µL)
- Incubate at room temperature for 20 - 60 minutes
- Read absorbance at 562 nm (in the range of 540-590 nm)
PREPARATION OF STANDARD SOLUTION
https://www.aatbio.com/tools/serial-dilution/11115
PREPARATION OF WORKING SOLUTION
- Prepare the amount of BCA working solution needed by mixing 50 parts of BCA Solution A (Component A) with 1 part of BCA Solution B (Component B) (50:1, v/v ratio of Solution A: B).
- Mix well until the BCA working solution is a uniform, light green color.
Note 1 mL BCA working solution is enough for 20 tests.
SAMPLE EXPERIMENTAL PROTOCOL
BS1 | BS1 | TS | TS |
BS2 | BS2 | ... | ... |
BS3 | BS3 | ||
BS4 | BS4 | ||
BS5 | BS5 | ||
BS6 | BS6 | ||
BS7 | BS7 | ||
BL | BL |
Well | Volume | Reagent |
BS1-BS7 | 50 µL | Serial dilutions (400-6.25 µg/mL) |
BL | 50 µL | PBS |
TS | 50 µL | Test samples |
- Prepare BSA standards (BS), blank controls (BL), and test samples (TS) according to the layout provided in Tables 1 and 2.
- Add 50 µL of BCA working solution to each well of BSA standard, blank control, and test samples to make the total assay volume of 100 µL/well.
- Incubate the reaction at room temperature for 20 to 60 minutes.
- Monitor the absorbance with an absorbance microplate reader at OD 562 nm (in the range of 540 to 590 nm).
Alternative formats
References
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