Tools / Biotech
Protein Concentration (A280) Calculator
Determine protein concentration using the Beer-Lambert law based on A280 absorbance, extinction coefficient, and molecular weight.
BSA is ~43,824.
Concentration
mg / mL
FAQ: Absorbance Measurements
- What causes high A280 readings without protein?
- Nucleic acid contamination heavily skews A280. Always check the 260/280 ratio. Pure protein should be ~0.57. For DNA yield, use our Plasmid Yield Calculator.
- Does buffer impact the reading?
- Yes. Buffer components like Triton X-100 absorb strongly at 280nm. Always blank with the exact buffer.