Image copyright University of Nottingham Image caption Prof Poliakoff achieved cult status after his chemistry videos became a hit

Two chemists, one who kicked off the development of Viagra and another who is a YouTube celebrity, have received knighthoods in the New Year Honours.

Dr Simon Campbell started and oversaw research on Viagra while working for the drug company Pfizer.

Prof Martyn Poliakoff is a pioneer in green and sustainable chemistry, known for his "Periodic Table of Videos".

Peter Kendall, former president of the National Farmers' Union (NFU), becomes a Knight Bachelor.

'Father of Viagra'

Dr Campbell was associated with three new drugs during his 26-year stint at Pfizer, all aimed at treating high blood pressure.

The last one turned out to have a valuable side effect because it improved blood flow to the penis - and it famously hit the market in 1998 as Viagra.

Image copyright Simon Campbell Image caption Dr Campbell became a Fellow of the Royal Society in 1999

But Dr Campbell was quick to point out that he was not the inventor of Viagra. He co-wrote the initial research proposal, with no mention of erectile dysfunction, before others took over the chemistry.

"I'm not on the Viagra patent," Dr Campbell told the BBC. "If you want, I would say I was the father of Viagra because I laid the seed and started the project.

"And I was there in New York, on my birthday in March 1998, when it was launched."

Dr Campbell was also the first chair of the Medicines for Malaria Venture, a landmark public-private partnership, which he said was a career highlight.

He said he had been especially proud to be elected as a fellow of the Royal Society in 1999 - an honour that is much rarer for scientists in industry rather than academia.

Dr Campbell reiterated concerns he has expressed previously about the increasing number of mergers and the size of pharmaceutical companies today.

"I don't believe you can manage innovation on that scale," he said, referring to research departments of thousands, rather than tens or hundreds of people.

"I like to work in groups of 100. I'm a great fan of the Roman centurion who had 100 men.

"When I had 100 chemists, I knew what they were all doing. When I had 200 chemists, it started to get a bit flaky."

Image copyright Getty Images Image caption When it research began in the 1980s, Viagra was aimed at treating angina and high blood pressure

Crazy idea

Prof Poliakoff said he was "excited and slightly overwhelmed" by the news of his knighthood.

By the time we finished, we had a lot of fans who said, 'Whatever you do, don't stop making videos!' Prof Martyn Poliakoff, University of Nottingham

The chemistry professor at the University of Nottingham, who is also foreign secretary and vice-president of the Royal Society, is recognised by many as the face of his online video series - a 2008 project of which he remains "very proud".

"We made 120 videos in five weeks," he told BBC News, crediting video journalist Brady Haran with the "crazy" idea of making a short film for every chemical element.

"By the time we finished, we had a lot of fans who said, 'Whatever you do, don't stop making videos'!"

So the team continued - adding more videos and presenters to a YouTube channel that has now notched up more than 80 million views.

Part of the charm, Prof Poliakoff concedes, is that he looks the part of an archetypal mad scientist.

"Even I have to admit that I look like... what people imagine scientists to look like," he said - adding that his unmistakeable hair and glasses have seen him approached by fans in the Paris metro and Beijing Airport.

The professor also takes pride in the progress his field has made, particularly in the UK.

"Green and sustainable chemistry has now become one of the principle research themes at my university," he observed.

"I'm really quite excited that what I started as a lone activity has now become a major activity."

'Massive honour'

One of leading figures in UK farming has also been recognised in the New Year Honours.

I was very keen that farming was seen as an innovative industry and one that was attractive to young people Peter Kendall, Former NFU president

Peter Kendall, former president of the National Farmers' Union, has been awarded a knighthood.

Mr Kendall, who headed the NFU for eight years between 2006 and 2014, said it was "a massive honour" to become a Knight Bachelor in recognition for services to the agricultural industry in England and Wales.

"Hopefully, it reflects the growing awareness of the importance of the farming industry," he told BBC News.

Mr Kendall, who is now chairman of the Agriculture and Horticulture Development Board (AHDB), said that he used his time at the NFU to try and change the image of the UK farming industry.

"I was very keen that farming was seen as an innovative industry and one that was attractive to young people.

"It is very pleasing that people now see that they can follow careers in farming and it is more relevant to the next generation."

Image copyright Getty Images Image caption Mr Kendall was president of the NFU for eight years

As was the case in the 2014 Birthday Honours, leaders in science and technology make up about 3% of the New Year Honours list, which includes 1,164 names.

Dr Vicky Robinson, Chief Executive of the NC3Rs (National Centre for the Replacement, Refinement and Reduction of Animals in Research) is appointed CBE for "services to science and animal welfare".

Neuroscientist Russell Foster, a professor at the University of Oxford who participated in the BBC's Day of the Body Clock, also becomes a CBE.

Climate physicist Prof Tim Palmer and wind-up radio inventor Trevor Baylis are also recognised with CBE awards.

Another Oxford professor and a former president of the Academy Medical Sciences, Sir John Bell, becomes a Knight Grand Cross - the highest class of knighthood - for his "services to medicine, medical research and the UK life science industry".

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