Professor Sir Ken Murray's work was credited with saving countless lives.
Sir Ken worked at Edinburgh University for more than 30 years and was one of the earliest researchers in genetic engineering.
He died at his home in the capital last April aged 82 and his published will reveals he had amassed a huge estate.
It included £13,333,058 held in the UK in his name and also a further £9.2m he inherited from his wife Noreen.
His will also shows he had a £22.5m estate outside the UK, the bulk of which was held with bankers Morgan Stanley in the USA.
Sir Ken ordered gifts totalling £3.4m should be given to friends, relatives and various academic organisations.
But he asked that the remainder should be left to the Darwin Trust, which he founded in 1983.
The charity supports the education of young scientists and helps to fund cutting-edge research and improve facilities at Edinburgh University.
Its chairman Dr John Tooze, 75, said it stood to receive around £30m.
He added: "He wasn't interested in living a celebrity lifestyle with his wealth.
"He wanted to see his money used for the benefit of other young scientists."