A research team from the Department of Chemical and Bioengineering at the University of Cambridge has succeeded in coming up with an innovative method, which will allow users of touch screens in smartphones and tablets to detect contaminants in drinking water in real-time before ingesting them by pouring a drop of water on the screen, according to the Cambridge Network technology.
The researchers demonstrated how touch screens are ideal for use in identifying common ionic pollutants in soil and drinking water, by dropping liquid samples on the screen. The results showed that the sensitivity of the touch screen sensor is comparable to laboratory equipment, making it useful for use in low-resource settings.
And Ronan Daly, a co-author of the study, explained that the screen of an ordinary smartphone is covered in a network of electrodes, as it is sensitive to interpreting the movement of a finger.
He stated that he and his team developed a method that allows smart touch screen technology to sense and read electrolyte ions in water and soil, as they interpret the movement of a finger, without the need to fundamentally change the screen.
The research team used computer simulations to validate the technology, using a touch screen specially made by two companies that manufacture touch screens in Britain, similar to those used in smartphones and tablets.
During the experiment, the researchers poured different liquid drops onto the screen to measure the change in the screen's capacitance and recorded the measurements from each drop using computer software to test the standard touch screen.
Experiments showed that all the ions in the liquids interact with the electric fields of the screen differently, depending on the concentration of the ions and their electric charge
Sebastian Horstmann, the first author of the study, explained that the simulations showed where the electric field interacts with the liquid drop noting that it is currently ideal for sensing ionic contamination in drinking water.
In current systems, the sensitivity of phone and tablet screens is adjusted to the fingers. The Cambridge researchers explained that this sensitivity can change in a specific part of the screen by modifying the electrode design of these screens to sense water and soil contamination.
The technology has theoretically proven that a drop of water can be added to the phone screen before drinking it, to make sure it is safe Horstmann said, stressing that one early application of the technology could be used to detect arsenic contamination in drinking water.
Arsenic is a common pollutant found in groundwater in many parts of the world, but most municipal water systems check and filter it before it reaches people's taps. However, parts of the world face the problem of dangerous arsenic contamination of water; Because of the scarcity of water treatment plants, it has.
The research team hopes to further develop the technology so that it can detect a wide range of harmful particles in water and soil, such as detecting heavy metals in water such as lead.
The researchers also anticipate that the new technology will one day be developed for a wide range of sensor applications, including for biological and medical diagnostics, directly from a smartphone in a user's pocket.
Previous research used the computing power of the smartphone in sensor applications but relied on the camera or external devices, as this required significant changes to the screen.