The separation of two critical pairs: 2-methyl-4-chlorophenoxyacetic acid (MCPA) and 2,4-Dichlorophenoxyacetic acid (2,4-D); and methylchlorophenoxypropionic acid (Mecoprop) and (R)-2-(2,4-dichlorophenoxy)propanoic acid (Dichlorprop) will be discussed. These broad leaf herbicides are difficult to separate on traditional HPLC columns. Herein, these two critical pairs, using a Diamond Analytics Mixed-Mode column, have been baseline resolved.  The presented work also discusses the retention mechanism of these herbicides and other acidic herbicides (dicamba and MCPB) as a function of their pKa at low pH.

Understanding the separation mechanism of acidic herbicides on the Flare Mixed-Mode C18 column

248th National Meeting (2014)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.