Non-ionic micellar solubilization - spectrofluorimetric determination of trace of germanium(IV) with quercetin in real samples

A spectrofluorometric method is described for the determination of germaniu m(IV) based on its complexation reaction with quercetin in presence of Brij -35. The fluorescence is monitored at 552 mn with excitation at 432 nm. The pH, quercetin and Brij-35 concentrations were optimized simultaneously usi ng the response surface methodology from sequential experimental three-vari able Doehlert designs. Interferences in this determination have been studie d. The detection limit is 7.4 ng ml(-1) and the linear range is between 7.4 and 150 ng ml-(1). The method has been applied to the determination of ger manium in a drug and in wholemeal oats. (C) 2001 Elsevier Science B.V. All rights reserved.