MIT7_13f08_lab02_Protocol_Agarose

MIT7_13f08_lab02_Protocol_Agarose - MIT OpenCourseWare...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: MIT OpenCourseWare http://ocw.mit.edu 7.13 Experimental Microbial Genetics Fall 2008 For information about citing these materials or our Terms of Use, visit: http://ocw.mit.edu/terms . 7 . 1 3 F a l l 2 0 0 8 P a g e | 1 Agarose Gel Electrophoresis and DNA Band Excision How it works: Agarose gel electrophoresis is a simple and highly effective method for separating, identifying, and purifying 0.5 to 25 kb DNA fragments. Voltage applied at the ends of an agarose gel generates an electric field with a strength defined by the length of the gel and the potential difference at the ends (V/cm). DNA molecules exposed to this electric field migrate toward the anode (positive end) due to the negatively charged phosphates along the DNA backbone. The migration velocity is limited by the frictional force imposed by the gel matrix. While charge and/or size can affect the rate at which macromolecules will pass through the gel, the charge to mass ratio is the same for DNA molecules of different lengths. It is the size of the DNA, therefore, that determines the rate at which it passes through the gel, thereby allowing an effective separation of DNA fragment-length mixtures by electrophoresis. To visualize the DNA, the gel is treated with ethidium bromide. This dye intercalates between the stacked bases of nucleic acids and fluoresces bromide....
View Full Document

Page1 / 5

MIT7_13f08_lab02_Protocol_Agarose - MIT OpenCourseWare...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online