Pyoverdin-doped sol–gel glass for the spectrofluorimetric determination of iron(III)

Abstract

Pyoverdin, a natural fluorescent pigment biosynthesized by Pseudomonas fluorescence, was entrapped in sol–gel glass and used as a reactive solid phase for the determination of trace amounts of Fe^III. No leaching or bleaching of the trapped reagent was observed. The fluorescent siderophore was more stable in sol–gel glass than on controlled-pore glass. Iron(III) was determined by continuous flow and flow injection (FI) methods. Both methods provided a fast response. The detection limits were 3 ng ml^–1(relative standard deviation, 3.0% for 150 ng ml^–1 of Fe^III) and 20 ng ml^–1(relative standard deviation, 4.5% for 500 ng ml^–1 of Fe^III) for the continuous and FI (sample injection 1 ml) systems, respectively. The selective sensor was successfully used to determine iron in tap waters (continuous system) and human serum (FI system).