ROBOTIC SAMPLE PRETREATMENT COUPLED WITH FLOW-INJECTION ONLINE SORPTION PRECONCENTRATION - ELECTROTHERMAL ATOMIC-ABSORPTION SPECTROMETRY FOR THE DETERMINATION OF COPPER IN ENVIRONMENTAL AND BIOLOGICAL-MATERIALS

An automated robotic method for sample pretreatment was der eloped for copper determination in environmental and biological materials at the low microgram per gram level. The robotic station performing the prel iminary operations as weighing of sample and acid digestion was couple d with the flow-injection (FI) on-line sorption preconcentration of th e pyrrolidine dithiocarbamate chelate of copper on the walls of a PTFE knotted reactor (KR) and subsequent electrothermal atomic absorption spectrometry (ETAAS) determination of copper. The accuracy of the meth od was demonstrated by the analysis of environmental and biological ce rtified reference materials. The precision is 1.4-2.5% relative standa rd deviation in the 4-50 mu g g(-1) concentration range. (C) 1998 John Wiley & Sons, Inc.