In Japan, monitoring of perchloric acid is required for drinking water quality control. The advisory level is assigned at 0.025 mg/L (April 2011 in Japan). In this application, RSpak JJ-50 2D was used for an LC/MS analysis of perchloric acid and oxyhalides. JJ-50 is modified with quaternary ammonium functional group and it works as a multimode column (reversed phase + anion exchange). By optimizing mobile phase composition and flow rate for LC/MS, 0.1ug/L perchloric acid can be detected under SIM mode.
Sample : 5μL
Column : Shodex RSpak JJ-50 2D (2.0mmI.D. x 150mm) Eluent : 50mM Ammonium formate aq./CH3CN=25/75 Flow rate : 0.2mL/min Detector : ESI-MS(SIM) Column temp. : 30°C