A robot fish that eats up plastic in the ocean is in contention for a youth tech prize.

Plastic

Plastic

Youngsters aged 11 to 16 came up with the idea to help combat the environmental issue that affects the world's oceans.

A total of 40 groups have been shortlisted for the Longitude Explorer Prize and another genius idea is a t-shirt which detects heart problems.

The winners will split £25,000, whilst runners-up can nab £10,000.

Science Minister Amanda Solloway said: "It is incredible to see how these young finalists have thought up innovations to tackle global challenges, from devices that detect health problems to robots which can remove plastic waste from our seas. "Technological innovation is important to grow the UK economy and we are supporting young people to pursue careers in this area through schemes like the Longitude Explorer Prize."

The teams will have to take part in a 'Dragon's Den' style pitch in July.