Which Swiss chemist prepared the highly purified Signer DNA sample?

Swiss chemist Rudolf Signer prepared the highly purified DNA sample later known as Signer DNA. He isolated it from calf thymus and distributed samples to researchers studying DNA’s structure.

Signer was an organic chemist and professor at the University of Bern. In 1950, he brought about 15 grams of exceptionally pure DNA to London for a Faraday Society meeting. Maurice Wilkins received some of the material, which was subsequently used in X-ray diffraction work at King’s College London.

The quality of Signer’s DNA mattered because clear, well-ordered fibres produced better diffraction patterns. Rosalind Franklin and Raymond Gosling later worked with DNA samples at King’s, including material connected with Signer’s preparation. Their diffraction studies contributed important evidence about DNA’s helical structure.

A common mix-up is confusing Signer with the people who analysed or used the sample. Alec Stokes and Franklin worked on diffraction-related research, while Erwin Chargaff studied DNA composition. Signer was the chemist who prepared the purified sample itself.