Dangerous mercury can now be detected in literally two minutes — even if there is almost none of it. Scientists from South Ural State University (SUSU) have developed a new method that "sees" the metal in ultra-low concentrations.
How the New Method Works
Scientists have created a special electrode that detects mercury ions in aqueous solutions. It is coated with a special material containing the rare earth metal praseodymium, which makes the sensor much more sensitive. It can detect mercury even in very small quantities — from one nanomole. This is approximately 200 nanograms per liter, which is below the level considered acceptable.
Why the Development is Important
The problem of water contamination with mercury remains one of the most dangerous in the world. This metal accumulates in the body and can cause serious diseases.
One well-known example is Minamata disease in Japan, which arose from industrial mercury discharges.
At the same time, detecting mercury in drinking water, soil, or products — such as tea and coffee — is extremely difficult. The maximum permissible concentration according to WHO standards is only 0.001 mg/l.
What Results Did the Sensor Show
The development by Chelyabinsk scientists showed high sensitivity and accuracy.
The sensor stably detects mercury in the range from 1 to 5 nanomoles. The detection limit is only 0.15 nM, which allows finding even trace amounts of the substance.
Even in the presence of other ions — lead, copper, iron — and organic substances, such as urea and phenol, the device did not give errors and accurately determined mercury.
Testing in Real Conditions
The method was tested on real samples.
Scientists added microscopic doses of mercury to tap water, soil, and extracts of tea and coffee. In all cases, the device showed high accuracy — the recovery rate ranged from 85% to 95%.
How is the Method Better Than Traditional Ones
In addition to accuracy, the development has two other important advantages — speed and accessibility.
Traditional methods require complex and expensive equipment, such as atomic emission spectrometers or chromatographs, the cost of which can reach tens of millions of rubles.
The new method uses a compact device.
Currently, studies are being conducted on a stationary potentiostat costing about 1.5 million rubles. Experiments are also underway with a portable sensor for about 300 thousand rubles, which can work with a laptop or even a smartphone. According to the developers, it will not be difficult to establish the production of such systems in Russia.
Where Will This Be Applied
The development may be in demand in environmental services. A portable analyzer will allow faster and less costly inspections, travel to pollution sites, and obtain results directly on site.
The method will also be useful for manufacturers of tea, coffee, and seafood — for rapid raw material testing.
There are also prospects in medicine. If the material is adapted for other biomarkers, sensors can be created for analyzing urine or sweat.
In addition, the technology can be used to control wastewater from industrial enterprises — especially in the chemical, mining, and leather industries — in real time.