The Amateur Scientist; January 1998; Scientific American Magazine; by Carlson; 2 Page(s)

Biochemists have always amazed me. Using mostly straightforward, inexpensive methods, these gifted researchers somehow manage to unlock many of the mysteries of life. And although the past decade has seen powerful (and expensive) new techniques brought to bear, discoveries are still being made by means that are well within the reach of a dedicated amateur. Sadly, biochemistry is a field that has so far been little explored by amateur researchers, and I think I know why. Few of them have access to what is perhaps the central tool of biochemistry--the centrifuge.

A centrifuge rapidly spins several small test tubes filled with a liquid suspension that is to be separated into its component parts. Like passengers in a car making a high-speed turn, every particle suspended within the tube is thrown outward by its own inertia. Biochemists often take advantage of this effect by adding something to a solution that causes certain components to precipitate. For purifying proteins, for example, this change is often provoked by adding a weak acid or base (vinegar or baking soda, for instance). The high "g forces" generated by the centrifuge then induce the solid particles to settle out in no time flat.