Interference studies in slotted silica tube trap technique

Abstract

Interference effects of KCl, NH4H2PO4, (NH4)2CO3, MgCl2, NH4NO3, NaNO3, (NH4)2SO4, MgSO4·7H2O, CaCl2, Ca(NO3)2 and NaCl on Bi, Cd, In, Pb and Sb were investigated using the atom trapping technique with a double slotted silica tube. Analyte solutions at concentration levels of 60, 6, 300, 75, 100 ng mL−1 for Bi, Cd, In, Pb and Sb, respectively, were aspirated into an air–acetylene flame and analyte species were collected on the silica surface. Revolatilization was effected by aspirating IBMK at the µL level. A method was proposed to classify interferences as the types of condensed phase or gas phase. In case of high NaCl content in the sample matrix, devitrification of the silica surface is a problem.