Sample Preparation
Protein samples can be derived from SDS-PAGE and are then subject to some chemical modifications. Disulfide bridges in proteins are reduced and cysteine amino acids are carboxymethylated chemically or acrylamidated during the gel electrophoresis.
Then the proteins are cut into several fragments using proteolytic enzymes such as trypsin, chymotrypsin or Glu-C. A typical sample:protease ratio is 50:1. The proteolysis is typically carried out overnight and the resulting peptides are extracted with acetonitrile and dried under vacuum. The peptides are then dissolved in a small amount of distilled water or further concentrated and purified using ZipTip Pipette tips and are ready for mass spectrometric analysis.
Read more about this topic: Peptide Mass Fingerprinting
Famous quotes containing the words sample and/or preparation:
“As a rule they will refuse even to sample a foreign dish, they regard such things as garlic and olive oil with disgust, life is unliveable to them unless they have tea and puddings.”
—George Orwell (1903–1950)
“Living each day as a preparation for the next is an exciting way to live. Looking forward to something is much more fun than looking back at something—and much more constructive. If we can prepare ourselves so that we never have to think, “Oh, if I had only known, if I had only been ready,” our lives can really be the great adventure we so passionately want them to be.”
—Hortense Odlum (1892–?)