Chromatographic Separation of Hydrophilic Organophosphates on a Porous Graphitized Carbon Sorbent Hypercarb Using an Aqueous Solution of Formic Acid As a Mobile Phase.

The possibility of the elution of hydrophilic organophosphorus substances using a concentration gradient of formic acid in an aqueous mobile phase on a Hypercarb porous graphitized carbon sorbent is studied. The analytes are detected on a monoquadrupole mass spectrometer. The retention of analytes is studied by varying the composition of the mobile phase before injection of the sample solution. It is shown that the effect of the stepwise gradient elution on the retention of analytes is primarily due to the state of the sorbent surface rather than the elution ability of the phases. The displacement "quasi-ion exchange" mechanism of analyte retention seems to be most probable. [ABSTRACT FROM AUTHOR]