Protein detection can be distinguished by several different methods, by which we have to separate whether we have fluids or tissue samples from a patient. The ongoing steps will be different. To understand the progress more easily let’s go through an example by which you try to find a protein (p53) in your samples. Basic methods for isolation and detection are:
- SALTING IN/OUT
- SONICATION
- CENTRIFUGATION
- ISOELECTRIC FOCUSING
- SDS-PAGE
- NATIVE-PAGE
- WESTERN BLOT ELISA
Salting in and out
In most of the cases, we got samples from a patient in the form of “SERO”-type samples or URINE samples respectively. In these samples, all the proteins are in a dissolved stage, from which we need to make an insoluble one. Regarding the blood samples, we need to centrifuge it first to separate the plasma-serum fractions. But in the case of the urine samples, we need to change the osmotic features of the solution. The basic method to make our proteins visible in a solution is to precipitate them. One method for this is the increasing concentration of salt (Figure 1).