A Highly Structured 1,10-Phenanthroline Arrayed Hydrophobic Sulfone Membrane Platform for the Rapid Determination and Speciation of Fe2+/Fe3+ Ions in Water

Abstract

An optical assay for the rapid determination and chemical speciation of Fe 2+ /Fe 3+ species has been proposed for the first time on a polyether sulfone (PES) membrane platform. The small pore size and low wettability (θ ~82 ) of the membrane disallowed the dissipation of analyte droplets on the surface, thus localizing it onto nanoliter arrayed 1,10-phenanthroline spots. Under optimized conditions and within ~5 min, an acceptable limit of detection (0.1 μg mL -1 ) and linear dynamic range (1 -100 μg mL -1 ) were achieved. The proposed method was also successfully applied for indirect determination of Fe 3+ ions in synthetic samples after reduction to Fe 2+ using SO2. The performance of the proposed sensor was validated for its robustness and stability. Due to high selectivity and accuracy, the method was satisfactorily applied for the analysis of Fe 2+ /Fe 3+ species in marine water samples. The proposed method is an easy and low-cost system coupled with good reproducibility and ruggedness, applicable for point-of-use testing.

Iron (II) Determination in Lipstick Samples using Spectrophotometric and Microfluidic Paper-based Analytical Device (µPADs) Platform via Complexation Reaction with Iron Chelator 1, 10-phenanthroline: A Comparative Study

“…2c reveals that the absorbance increased with pH increasing and reached the maximum at pH 5.0 for iron complexes this can be attributed to low hydrogen-ion activity, which avoids the nitrogen atoms protonation leading to strong bond formation. Afterwards, the absorbance gradually decreased because a higher pH deters iron ions into iron hydroxyl species that alter the complexion between Iron metal and phen 36,37 .…”

“…All experiments were done using 80 mg L -1 of iron solution. The Effect of 1,10-phenanthroline Volume: Experiments on the influence of spotted reagent volume were done as the insufficient volume may lead to absorbance reduction at the same time the excess of volume may cause to solution spread outside the detection zone 36 . Phen 0.04 M volume was examined in the range (1-9) µL.…”

Mutual Separation of Fe(II) and Fe(III) Using Cyclohexane/Water/ Ionic-liquid Triphasic Extraction System with 2,2′-Bipyridine and Tri-n-octylphosphine Oxide

“…For determining the iron concentration in aqueous solution, several colorimetric methods have been reported with using thiocyanate ion, [3][4][5][6] 1,10-phenanthroline (phen), [7][8][9][10][11] 2,2′-bipyridine (bpy, Fig. 1) 12,13 and so on.…”