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 FeIII. 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 FeIII) and 20 ng ml–1(relative standard deviation, 4.5% for 500 ng ml–1 of FeIII) 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).