Particle Electrophoresis in Closed-both-end Capillary and Like Charged Particle Aggregation Induced by AC Electric Field

摘要

An alternative solution to the zero electroosmotic flow (EOF) capillary electrophoresis (CE) is proposed. First, flows in a capillary are decomposed and measurement results reconstructed. Second, CE "markers" are developed as reference. Third, the system is calibrated and crosschecked. Finally, costs of the alternative solution are evaluated. This report marks the beginning of these orchestrated efforts. A closed-both-end bare fused silica capillary as a model system has created informative data of DC or AC particle CE with the dilute suspension of carboxylated polystyrene spheres in deionzed water. The apparent electrophoresis mobility of a particle strongly depends on the DC electric field. In an electric field range from 5 to 10 V/cm, the particle motion becomes at random; the particle mobility first increases to 7×10~(-8) m~2(sV)~(-1) and then levels off in the DC electric field of 10 to 110 V/cm. These particles are induced to aggregate into clusters by an AC electric field in some frequency bands.