Starcher assay

There are men who have the courage to overthrow kings. The Texan Barry Starcher is such a man. His goal is—at least in my estimation— to dethrone the citation king Lowry with a 

In its details, this works as follows. The sample (tissue or protein solution) is hydrolyzed to the amino acids over 24 h in microfuge tubes with 0.5 ml 6-NHCl at 100° C. Starcher dries the hydrosylate on the speed-vac and dissolves it again in water. An aliquot is then pipetted onto a microtiter plate and ninhydrine reagent is added. Starcher lets the plate float for 10 minutes in a boiling water bath, whereupon the assay is done and can be read in the microplate reader. 

Disadvantages It takes 25 or 26 h until you can read your result. In addition, you have to manipulate the sample repeatedly hydrolyze, speed-vac, pipette, centrifuge, pipette, heat up. This is not only a test of your patience exactness also suffers. Hence, I fear that the Starcher assay will not be able to reach a similar number of citations as the Lowry. However, it makes the impression of being reliable, and if you need a protein determination with low protein-to-protein variation I would recommend it. 

Starcher, B. (2001). A Ninhydrin-based Assay to Quantitate the Total Protein Content of Tissue Samples, Anal. 

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Figure 1.4. Comparison of results of ninhydrin and Bradford methods for total protein concentration in tissue samples. Proteins in both assays are the same.8 [Reprinted, with permission, from B. Starcher, Anal. Hiochem. 292, 2001, 125-129. A Nirhydrin-Based Assay to Quantitate the Total Protein Content of Tissue Samples. Copyright 2001 by Academic Press.]...

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