Capacitively coupled microwave plasma atomic emission spectrometer for the determination of lead in whole blood.
The determination of lead in whole blood by atomic emission spectrometry using a capacitively coupled microwave plasma and a tungsten filament electrode is presented. When the plasma-supporting electrode is also used as the sample holder, transfer of the sample to the plasma is 100%. Microwaves are used to dry the sample and, at higher powers, ignite a helium plasma which results in the atomization and excitation of Pb. Using this methodology, a detection limit of 3 pg of Pb was obtained using 5-microL aqueous samples. The precision was 9%. Whole blood samples were subjected to a drying stage similar to that of the aqueous samples. Following this drying stage, a low-power (30 W) helium plasma was ignited and used to ash the blood sample. Higher power plasmas (> 150 W) were used to atomize and excite the Pb. Recovery of Pb from the blood samples was 88%, when compared to aqueous standards.
Wensing
M W
MW
Department of Chemistry, University of Florida, Gainesville 32611.
Smith
B W
BW
Winefordner
J D
JD
D002138:Calibration; D004566:Electrodes; D006801:Humans; D007854:Lead / Q000097:blood*; D008872:Microwaves; D013057:Spectrum Analysis / Q000379:methods*; D014414:Tungsten
D007854:Lead; D014414:Tungsten