Sequential extraction--spectrofluorometric determination of lead and cadmium using cryptands.
A spectrofluorimetric method for the determination of ultratrace amounts of lead and cadmium is described based on the sequential extraction of the ternary ion-association complexes formed between the cation, a cryptand as the ligand and eosin as a counter ion. A linear working range from the detection limit (0.5 ng ml(-1) to 250 ng ml(-1) of lead and to 1 50 ng ml(-1) of cadmium was obtained. The relative standard deviation was 2-4%. The proposed method has been applied successfully to the determination of lead and cadmium in zinc metals and soft drinks.
Departamento de Quimica Fisica, Universidad de Oviedo, Spain.
D B
DB
Gomis
E A
EA
Garcia
D001643:Bridged Bicyclo Compounds; D019086:Bridged Bicyclo Compounds, Heterocyclic; D001952:Bridged-Ring Compounds; D002104:Cadmium / Q000032:analysis*; D002253:Carbonated Beverages / Q000032:analysis; D002412:Cations; D002614:Chelating Agents; D004801:Eosine Yellowish-(YS); D007202:Indicators and Reagents; D007854:Lead / Q000032:analysis*; D013050:Spectrometry, Fluorescence
D001643:Bridged Bicyclo Compounds; D019086:Bridged Bicyclo Compounds, Heterocyclic; D001952:Bridged-Ring Compounds; D002412:Cations; D002614:Chelating Agents; D007202:Indicators and Reagents; D002104:Cadmium; C006071:cryptating agent 222; D007854:Lead; C053547:cryptating agent 221; D004801:Eosine Yellowish-(YS)