What are electrophoresis units? What are they used for?

Question

What are electrophoresis units? What are they used for?

Answer 1

It's a simple machine used for running gel electrophoreses.

http://www.topac.com/images/hu6_250.jpg

That's a picture.

It's basically a tray, filled with buffer (that has electrolytes in it to transmit the electric current), with two electrodes - an anode and a cathode.

When you link the electrodes to an energy source with a voltmeter, you can send a certain amount of electricity through the buffer.

When you put a gel in the tray, it is totally submerged in the buffer. You load DNA samples and a base pair ladder into indentations in the gel, and turn on the electricity. Since DNA is slightly negatively charged, it migrates towards the positive electrode.

The gel has fibers in it that slow the molecules down, so smaller DNA molecules go further in a set time than larger ones.

This allows for separation of DNA molecules by size.

This is useful when you use a certain DNA-chewing enzyme, that breaks the DNA strands at certain target nucleotide sequences. You can tell roughly how many target sequences there are in the sample by counting the number of bands you get in a certain "lane" on the gel.

Answer 2

Electrophoresis units are machines that can separate a mixture suspended in a support medium by the size of the suspended particles. It does this by applying a electric field, which attracts the particles by electrostatic force. However, as the size of the particles increase, increasing friction slows their movement. When finished, the smallest particles are the closest to the positive and negative ends of the unit, while the larger ones are stuck near the point of origin (usually the center).

These machines are inexpensive and useful in separating out organic molecules, specifically RNA and DNA. Electrophoresis is commonly used to identify and filter out specific fragments, which would otherwise be very difficult and laborious to do.