Journal articles made easy: Detecting iron


This article looks at measuring iron in a variety of solutions using a scalable RGB technique. It will help you understand the research the journal article is based on, and how to read and understand journal articles. The research article was orginally published in Journal of Materials Chemistry A.

Type of Activity

working independently



Age Group

Undergraduate & Postgraduate

Dr José M. García, the lead author of the article, answers some additional questions on his group's work.

What inspired the use of the RGB values as a quantitative technique?

The main goal of our research is to prepare materials by design, i.e. with some properties or characteristics in mind, preparing a material to achieve these technological demands. Regarding this work, our main aim was preparing a material for the visual detection and broad quantification of iron. Our eyes are precise for detecting colours and are obviously valid for analytical purposes. We can detect a colour change and, with a reference, broadly estimate concentrations, for example think of a pH litmus paper, or in  a yes/no pregnacy test. Once a broad estimate is made, our second goal was the use of a conventional device to quantify finely the concentration of the chemical. A conventional digital picture has the colour information taken from a sensory disk, and the RGB parameters can be used to build a calibration curve. If you use a smartphone, the RGB parameters can be directly obtained from the phone. Rapid, cheap, and easy to use from non skilled personnel.

How flexible do you see this technique being for other metals/analytes?

We are working on detecting different chemicals: anions, cations, and neutral molecules. For instance, we are now preparing a paper for visually detecting explosives for civil security purposes. Please see our recent paper in Anal Methods.

In your own words, what do you feel is the highlight of this work?

The design of the sensory material- this is the key to the performance. It is solid, it is sensitive to Fe(III) and can be managed without care, etc.

What do you feel was the biggest challenge in the study?

It is again the capability of preparing materials "a la carte" to achieve technological demands.

How would you like to develop this research in the future?

We have in mind important target molecules to detect for use in civil security, food security and medical fields. Think, for instance, of its use in intelligent fibres that in a garment change colour if a chemical, an explosive, for instance, is in the atmosphere, or intelligent labels for detecting the freshness or the contamination of foods, to name but a few.

How stable are the polymer disks? Do you foresee any issues with storage or usage in the field?

Fully stable for long period of time. The materials can be stored under conventional conditions for months or years.


Journal articles made easy are journal articles from a range of Royal Society of Chemistry journals that have been re-written into a standard, accessible format. They contain links to the associated Chemistry World article, ChemSpider entries, related journal articles, books and Learn Chemistry resources such as videos of techniques and resources on theory and activities. They should facilitate students understanding of scientific journal articles and how to extract and interpret the information in them.