Meet the hydrogel tablet. It purifies water in less than an hour!

Estimated reading time: 3 to 4 minutes

According to some estimates, half of the world's population could live in water-stressed areas by 2025. Hopefully, a solution may be found: a hydrogel tablet could save millions of people. Read more. 

One of the causes of child mortality and various other diseases e water scarcity worldwide 

Water without any microorganisms is a fundamental right for any human being upon Earth, no matter whether they are poor or not.  Actually, it is a gift from mother nature. Yet one-third of the world's population has no access to it at all.

The poorer the region, the worse is the situation due to the lack of environmental education for the local population. In short, finding a solution to this problem became a high priority among scientists and engineers around the globe. 

The crisis regarding good water is worse when locals have no access to piped water or decent sanitation.

4 alternatives to purifying water that takes more work and is not always totally effective:

1 - Boil or pasteurize

A popular way to purify water is widely used in both food and personal hygiene. Although it partly solves the problem. Hydrogel tablets work faster and require less work (like going to some river in order to collect water). The process of cleansing water takes approximately one hour.

2 - Solar desalination

During solar energy usage, vaporization helps separate impurities from salty water. However, this process is expensive mostly when sunlight is rare, as in colder regions, and diminishes the rate of steam generation. A similar problem occurs with seawater desalination, 

3 - Chlorine, ozone, or flocculation

Water disinfection using these chemicals is common and low cost. However,  this cheap can get expensive. That's because the products may generate the formation of other toxic by-products that pop up during the distillation of thermal-based water.

4 - Sanitary water

The so-called "inorganic chlorine" has its disinfectant effectiveness reduced as the pH increases. In other words, when an unstable salt originating from a weak acid with a strong base prevails, the tendency is for alkalinity at a very high rate of pH values. This will limit its germicidal action. 

If the packaging of the above-mentioned products is in plastic containers, it releases toxic substances (the same happens to the water reconditioned in plastic bottles, unless, of course, the plastic is sustainable). 

How the hydrogel tablet was discovered for water purification

A highly vigilant graduate student, Youhong Guo, discovered these hydrogels while doing something else!

Youhong (Nancy) Guo, a graduate student in Materials Science and Engineering at the Texas Materials Institute at the University of Texas, discovered, by chance, another use for a tablet made of antibacterial hydrogel (based on catechol, a plant-derived substance used in aesthetic medicine).

When she came across the results, she contacted her professor right away!

“Our multifunctional hydrogel can make a big difference in mitigating global water scarcity because it is easy to use, highly efficient, and potentially scalable up to mass production,” said Guihua Yu, an associate professor in the Cockrell School of Engineering’s Walker Department of Mechanical Engineering and Texas Materials Institute.

The goal is to increase the hydrogen's range so it can eliminate diverse strains of microorganisms.

How the hydrogel works

The hydrogel produces hydrogen peroxide that neutralizes bacteria at an efficiency rate of nearly 100 percent.

In the process, activated carbon particles attack directly the bacteria cells, altering their metabolism by preventing the cultures from advancing. A single hydrogel tablet (the size of an ordinary pill) can disinfect a liter of water collected directly from a river.

Water treatment systems in the world today are expensive because they require complex infrastructures and excessive expenditure on electricity.


Manufacturing hydrogel tablets is pretty simple because according to the researchers, the materials to make them are cheap. Their free distribution could well be funded by governments at all levels. The larger the size of the tablet, the greater the amount of purified water.   

So far the scientists intend to work on prototypes so that the hydrogel tablets can be marketed and distributed worldwide. Who knows, a new revolution is just beginning to end once and for all the lack of good water for all?

By Marco Veado - THINK GREEN