Techniques to measure iron concentrations in blood samples are important diagnostic tools as abnormal iron levels are linked to numerous pathological conditions. Similarly, as iron can affect the quality of wine, it is important to measure its level during wine-making processes. Nevertheless, the strategies currently employed to quantify iron in blood or wine are not optimal.

This issue prompted Saúl Vallejos and colleagues, Universidad de Burgos, Spain, to develop an visual detection kit for iron that is based on a sensory polymeric material. The researchers transformed 8-hydroxyquinoline, an Fe^III chelator, into an acryl monomer and subsequently polymerized it with hydrophilic co-monomers. In this way, the scientists obtained disc-shaped polymeric membranes that worked as colorimetric chemosensors of Fe^III. Once immersed in aqueous solutions, such as blood serum or wine, the colorless and transparent discs acquired a green-brownish color, which was proportional to the amounts of Fe^III present in the samples.
After being digitalized with a camera and elaborated with a computer, the color of the discs provided a fast and accurate measurement of Fe^III concentrations.

• Solid sensory polymer substrates for the quantification of iron in blood, wine and water by a scalable RGB technique,
  Saúl Vallejos, Asunción Muñoz, Saturnino Ibeas, Felipe Serna, Félix Clemente García, José Miguel García,
  J. Mater. Chem. A 2013, 1, 15435–15441.
  DOI: 10.1039/C3TA12703F