Application of Soluble Membrane Filter in Simultaneous Determination of Trace Levels of Cadmium, Copper, Lead and Zinc in Food Additives by Inductively Coupled Plasma Atomic Emission Spectrometry

摘要

A method for simultaneous determination of trace levels of Cd(II), Cu(II), Pb(II) and Zn(II) in food additives by inductively coupled plasma atomic emission spectrometry ( ICP-AES ) after soluble membrane filter pre-concentration was developed. Based on collection of the chelates of metal ions(II) with 2-(5-bromo-2-pyridylazo)-5- diethylaminophenol ( 5-Br-PADAP ) on soluble membrane filter, the analyte ions were pre-concentrated and separated from sample matrix solutions. Multi-channel membrane filter device and soluble mixed cellulose ester membrane were selected. Analytical parameters such as pH, amount of 5-Br-PADAP, sample volume, etc. were optimized.