Jun 13, 2016
Lowry Protein Assay
- David Dunigan and Irina Agarkova1
- 1University of Nebraska-Lincoln
- VERVE Net
- Fish behavior and physiology
Protocol Citation: David Dunigan and Irina Agarkova 2016. Lowry Protein Assay. protocols.io https://dx.doi.org/10.17504/protocols.io.etxbepn
License: This is an open access protocol distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited
Protocol status: Working
Created: April 05, 2016
Last Modified: September 09, 2020
Protocol Integer ID: 2647
Guidelines
Materials:
- Reagent “A” - 2.0% Na2CO3 in 0.1 N NaOH
- Reagent “B” - 0.5% CuSO4.5H2O in 1.0% Na citrate
- Reagent “C” - 50.0 mL reagent “A” + 1.0 mL reagent “B”
- Reagent “D” - Folin-Phenol Reagent (2 N Solution, Folin/Ciocalteau), dilute 1:1 with d-H2O before using
Notes:
It may be possible to reduce the initial volume of each assay to 0.5 mL and thus reduce the amount of subsequent reagents used by 50%. Use the same amounts of BSA for the protein standard curve.
Set up a standard curve of 0, 10, 25, 50, 100, 150 and 200 µg of BSA in 10-15 ml tubes, 1.0 mL volume per sample.
Set up tubes (10-15 mL) of the unknown protein sample(s) to determine their concentration, the final volume per sample is to be 1.0 mL.
Note
May need to dilute the sample(s) so that some reactions are in the concentration range of the standard curve values.
Add 5.0 mL of reagent “C” to each tube, mix immediately.
Let the samples sit for 10 min at room temperature.
00:10:00
Add 0.5 mL of reagent “D” to each tube, mix immediately.
Let the samples sit for 30 min at room temperature.
00:30:00
Read absorbance at 600 nm. Record values, plot standard curve and determine sample concentration(s).