Detection of ultratrace phosphorus and sulfur by quadrupole ICPMS with dynamic reaction cell

摘要: A method of detection ultratrace phosphorus and sulfur that uses reaction with O2 in a dynamic cell (DRC) to oxidize S+ P+ allow their as SO+ PO+ is described. The reduces the effect polyatomic isobaric interferences at m/z = 31 32 by detecting product oxide ions are less interfered. Use an axial field DRC improves transmission 4−6 times. With no field, limits (3σ, 5-s integration) 0.20 0.52 ng/mL, background equivalent concentrations 0.53 4.8 respectively, achieved. At optimum potential (200 V), 0.06 ng/mL for P 0.2 S, respectively. used determining degree phosphorylation β-casein, regular dephosphorylated α-caseins 10−1000 fmol/μL concentration, 5−10% v/v organic sample matrix (acetonitrile, formic acid, ammonium bicarbonate). measured phosphory...