Pulsed field electrophoresis

✍ Scribed by Gregory T. Dee

• Publisher: Wiley (John Wiley & Sons)
• Year: 1988
• Tongue: English
• Weight: 493 KB
• Volume: 27
• Category: Article
• ISSN: 0006-3525
• DOI: 10.1002/bip.360270910

✦ Synopsis

Pulsed field electrophoresis, or PFE, provides good separation between large molecules that under constant field electrophoresis are hard to isolate. This is due to the weak dependence of the constant field mobility on the molecular weight for these large molecules. If a spectrum of relaxation times exists that describes the recovery of the mobility to its constant field value after a reversal of the field, then we show that molecules with differing molecular weights are separated into two groups. Those with short relaxation times are unaffected by the cycling of the field and those with long relaxation times exhibit reduced mobilities. If the molecules adopt conformations that decrease their mobility initially, after a field reversal we demonstrate that a minimum develops in the mobility as a junction of the relaxation time. Using the model we demonstrate that effects of varying the switching times as a function of time. We predict that exponential rather than linear dependencies of the switching times on time increase the range of molecular weights over which enhanced separation can occur.