Direct determination of macromolecular charge by equilibrium electrophoresis
Charge is a fundamental property of macromolecules in solution. However, estimation of the apparent charge on polyions has confounded science for decades. Presented here is a general method to determine directly the apparent charge on a polyion, regardless of its size or shape. This new method uses equilibrium electrophoresis, a procedure in which opposing solute flows from electrophoresis and from diffusion balance everywhere as the system reaches a steady-state distribution. The method uses only small quantities of materials, is nondestructive, and requires only simple, inexpensive instrumentation. Here we describe a prototype apparatus, demonstrate the phenomenon, and present experimental examples of the procedure.
Molecular, Cellular and Biomedical Sciences
Digital Object Identifier (DOI)
Laue, T.M., Hazard, A.L., Ridgeway, T.M, and Yphantis, D.A. (1989) "Direct Determination of Apparent Charge on Macromolecules by Equilibrium Electrophoresis." Anal. Biochem., 182, 377-382.