Figure 1.
Injection mechanism for anionic compounds when using (a) field-enhanced sample injection (FESI) for an anionic compound at time 0 (when a water plug is initially injected by pressure) and time tmax (when the stacking boundary has retreated to the sample vessel) or (b) electrophoretic injection with a capillary containing a neutral coating, as used in this current study. The shaded regions on the right of each figure represent the region that contains the running buffer; the light regions to the left represent the sample solution and a plug of water that has been previously placed in the capillary, both of which have a much lower concentration of ions than the running buffer. The term EOF refers to the electroosmotic flow of the system.