Preliminary investigation of sintered plates bonded or end-capped with phenyl for planar electrochromatography

Two new types of reversed-phase sintered plate have been prepared used in planar electrochromatography (PEC). One was bonded with phenyl, instead of octadecyl, without end-capping or with different amounts of end-capping and the other was bonded with octadecyl and then end-capped with phenyl instead of methyl. Both worked well with mobile phases containing no buffer salts, and high potential could be used with low Joule heating. Four dyes were used as samples to examine the characteristics of these two types of plate in planar electrochromatography. The former was unsatisfactory but the latter gave satisfactory results. Our preliminary work revealed that suitable bonding of octadecyl was from 0.03 to 0.06 whereas suitable bonding of phenyl for end-capping was from 0.005 to 0.02, which was readily achieved.