Sir Christopher Evans, the third man arrested over the "cash-for-honours" allegations, is widely regarded as one of Europe's leading biotechnology entrepreneurs.
Sir Christopher Evans has spent 25 years in the biotech sector
Knighted in 2001 for his services to the sector, after earlier being given an OBE in 1995, he runs a venture capital company called Merlin Biosciences.
Founded in 1996, it manages or advises more than £270m of investments in the biotechnology industry.
In total he has established 20 science companies in his 25 years in the industry, of which four have floated on the London Stock Exchange.
The firms Sir Christopher has founded have a combined value of £1bn and employ 2,000 people.
Stem cell research
Sir Christopher made a £1m loan to the Labour Party between January and May 2005.
In March 2005 he was appointed to the UK Stem Cell Initiative, a programme set up by Chancellor Gordon Brown to advise the government on the cutting-edge technology.
Mr Brown and Prime Minister Tony Blair were later named as backers of the UK Stem Cell Foundation, a charity set up by Sir Christopher.
Educated at London's Imperial College, where he obtained a degree in microbiology; he went on to gain a PhD in biochemistry from the University of Hull, and research fellowships from the University of Michigan.
Twice voted Cambridge Businessman of the Year, Sir Christopher is known to have a keen interest in the wider small business sector, being a member of committees and trusts including the Prime Minister's Council for Science and Technology, and the National Enterprise Campaign.
Sir Christopher said he was "extremely shocked and dismayed" to be arrested in the "cash-for-honours" inquiry.