Determination of trace germanium by spectrophotometry after preconcentration on an organic solvent-soluble membrane

A sensitive and selective method for the determination of germanium in herb and water samples after preconcentration on an organic solvent-soluble mem brane was developed. After conversion to the ternary complex with o-nitroph enylfiuorone (o-NPF) and sodium dodecyl sulfate (SDS), germanium could be c ollected selectively on a membrane. The membrane was then dissolved in a sm all volume of 2-methoxyethanol for directly measuring the absorbance. By pr econcentration, the limit of detection for germanium was found to be 0.4 mu g l(-1) (0.4 ppb). The method was successfully applied for the analysis of Chinese herb, natural water, drinking water as well as urine samples. (C) 2000 Elsevier Science B.V. All rights reserved.