Many people don't have regular access to clean water. But in an effort to help make safe drinking water more readily available, an international team of scientists has created a portable water purifier that works simply by shaking it for three seconds and setting it to float. 

This could be a breakthrough device for water treatment in emergency situations and, best of all, it’s estimated to cost less than $25 to produce.

This low-cost and simplicity of operation disguise the sophistication of the science involved however: shaking the canister generates enough power for it to auto-analyze the water and activate an appropriate disinfection process. It then floats in the liquid and, as it bobs, movement of water against its surface creates an electrostatic charge that kills microbes.

That extraordinary combination of processes can disinfect a liter of water in 20 minutes to provide reliable safe drinking water without needing any chemicals, battery or external power source.

Just three seconds of shaking is enough to jostle the built-in magnet through a copper coil to generate enough current to power an internal electric field and sensor. This analyzes a small sample of the water in the canister by measuring the amount of dissolved material in the water, mostly ions such as salts and minerals. The device registers this as a warning signal for possible chemical contamination.

If the water measures below 250 milligrams of ‘total dissolved solids’ per liter, that’s the green light. The canister treats the water as low contamination risk and proceeds to microbial disinfection. If the reading is higher, it flags the water as unsuitable and you have to find another patch of water. While it’s good at killing microbes, the system can’t deal with a chemical contaminant, like an arsenic spill, pesticides or industrial pollutants.

Assuming the purifier senses that the water is okay to purify, the next step begins. As it bobs along, the water laps against the plastic shell. This generates a tiny electrostatic charge, like when you rub a balloon against your clothing. The plastic surface becomes positively charged and the water becomes negatively charged. And here’s the clever bit: the surface on the outside of the capsule is covered with microscopic polymer ‘nanorods’ whose tiny tips concentrate the charge into minuscule but very strong electric fields. They’re powerful enough to damage any microbes in the water nearby. The process of destroying them by breaking open their bacterial membranes is a little-known but established science known as electroporation.

The significance of the process is massive. More than two billion people around the world lack the safe normal drinking water. Add in emergency disaster situations and the potential applications of this device are huge!

Read the story for the full details: https://newatlas.com/outdoors/detect-disinfect-water-capsule-floating-shake/