Electrophoretic concentration of macromolecules

✍ Scribed by W.B. Allington; A.L. Cordry; G.A. McCullough; D.E. Mitchell; J.W. Nelson

• Publisher: Elsevier Science
• Year: 1978
• Tongue: English
• Weight: 564 KB
• Volume: 85
• Category: Article
• ISSN: 0003-2697
• DOI: 10.1016/0003-2697(78)90289-0

✦ Synopsis

An apparatus for concentrating macromolecules and removing macromolecules from nonionic solutes electrophoretically has been developed. Typical applications and techniques are outlined. Concentrations from 24 to 50-fold were achieved in a short period of time. The nondisruptive nature and versatility of the system is shown by the concentration of bovine serum albumin and three different enzymes.

Concentrating macromolecules

in fractions from chromatographic and density gradient electrophoresis columns, density gradients, etc., is often time consuming and difficult, especially for dilute solutions. Current methods are based upon precipitation, evaporation, filtration, or dialysis. These methods work well for many applications but may waste, inactivate, or contaminate the sample. The purpose of this study was to find an alternative method that would be fast, efficient, and nondisruptive. The method and apparatus2 developed are based on electrophoresis and filtration and will concentrate charged macromolecules and separate them from uncharged molecules such as sucrose.

A device designed by Posner (1) used electrophoresis and sedimentation to concentrate large volumes of sample. However, Posner's design is not suited for removal of sample from an uncharged medium such as sucrose. Other devices (2-6) are known which are specifically designed for removing samples from gels but none are optimized for concentrating the sample after removal from the gel.

Methods

The electrophoretic apparatus consists of three basic components: a sample cup, an electrophoresis tank, and a power supply offering the option of constant power.