Butterfly enthusiast Neil Bailey was one of dozens of fledgling entrepreneurs seeking investment at Venturefest, Oxford's annual festival for inventors and early-stage hi-tech businesses.

Dr Bailey and his Oxford Brookes University colleague, ecologist Dr Stewart Thompson, need £100,000 to expand their company WildKey, which provides hand-held computers for schoolchildren to identify wildlife.

Dr Bailey said: "If they see a Red Admiral the computer asks them questions like 'What colour are the wings?' and they see a photo so that they can record it."

The investment would allow WildKey to build up its workforce and branch out into offering visitor information for wildlife attractions.

Other business ideas at Venturefest included a pollution-reduction system, wireless laptop connectivity, new antibiotics, brain-surgery robots, gearshift technology with no power loss, and a tumour-inhibiting drug.

Tom Hockaday, of Oxford University's technology transfer company, Isis Innovation, was at the event at the Said Business School, celebrating the university's new £12m deal with City hedge fund Sloane Robinson to build a new biomedical engineering institute.

The institute, due to open next year at the Churchill Hospital, in Headington, is hoping to repeat the success story of the 'Oxford knee', an artificial joint developed by researchers John Goodfellow and John O'Connor.

Mr Hockaday said: "This deal reflects the value placed on Oxford technology and our capabilities in commercialising that technology."

Sloane Robinson has created a new division called Technikos to run the venture, hoping to develop Oxford biomedical inventions such as a device to extend the time a kidney can remain viable outside the body.

As well as patenting the Oxford knee, Oxford biomedical research has already spun out three companies Powderject, Oxford Biosignals and Mirada Solutions.

Prof Richard Darton said Powderject inventor Prof Brian Bellhouse had donated £1.3m towards the institute, which will cost £50m. He added: "The new building and research programmes will bring together engineers and clinicians, in a world-class facility, to tackle important illnesses like cancer and heart disease."

Tim Smit, founder of the Eden Project in Cornwall, spoke yesterdaymon at Venturefest, which also provides advice sessions, including guidance for doing business overseas.

The event brings together financiers, inventors, scientists, researchers and business service providers to support innovators, either through funding or through free guidance and resources.

Special exhibits include the Oxford Trust's Innovation Awards Exhibition, showcasing Oxfordshire schools' A-Level design and technology projects, and the Technology Showcase, a one-day exhibition of hi-tech companies.

Venturefest, which ends today, is free to attend.