Electrical Potential as a Driving Force in Sample Preparation

摘要

we are all familiar with the role of electromigration in enhancing separations in capillary and gel electrophoresis and related techniques and in capillary electro-chromatography. In addition, electrical potential has been used in electrochemical and other forms of chromatographic detection. The use of electrical potential to enhance and add another dimension of selectivity to sample preparation is still a relatively new, noncommercialized technique. The purpose of this installment is to discuss how electrically driven enhancement has already proven to offer some major advantages to the preparation of samples whose analytes of interest are ionized or can become ionized by the appropriate adjustment of pH to the separation media. We explore five sample preparation methods where the application of a charge across barriers provides enhanced selectivity, oftentimes leaving undesired matrix and impurities behind, thereby accomplishing the goals of sample preparation.