John S. Fawcett

Electrofocusing in Wide pH Range Immobiline Gels Containing Carrier Ampholytes

Summary Polyacrylamide gels covalently bonded with Immobiline (LKB) of a wide pH range (4-10) exhibit problems due to low conductance regions within the pH gradient such as slow migration rates across the pH extremes leading to substantial lateral zone diffusion and difficulties in pH measurement. An attempt was made to overcome these problems by the addition of carrier ampholytes to the gel. Parallel electrofocusing experiments with and without such additions were carried out to evaluate performance with regard to migration rates, zone sharpness, pH measurement and the emergence of a cathodic drift. Addition of carrier ampholytes resulted in a relative equalization of the conductance profile across the pH gradient, allowing for a more rapid protein entry, a diminished lateral band spreading and the feasibility of direct pH measurement.