“The water bottle contains two chambers. Dirty water is put in an outer chamber and the inner chamber is plunged through it, filtering water particles as small as four microns.
“Once filtered, the water is sterilised by a wind-up ultraviolet bulb in a process lasting 90 seconds.
“A prototype was effective in killing 99.9% of bacteria and viruses.
“Professor Matthew Harrison, who is one of the judges and also director of education programmes at the Royal Academy of Engineering, commented: “Pure provides a practical solution to a real problem – how to get clean drinking water in the most hostile of conditions.
“It has the potential to make a real difference to people’s lives.”
read more: BBC