In 1906, after Pierre's death, Marie decided to devote all her energy into their scientific research. She was appointed the professorship left open by her husbands death and became the first woman to teach at Sorbonne.
The University of Paris and the Pasteur Institute decided in 1909 to jointly build the Radium Institute. The institute comprised of 2 divisions, the Curie Laboratory (run by Marie) and the Pasteur laboratory. When it was completed in 1914 she became its first director.
In 1911 Marie Curie was awarded the Nobel Prize for chemistry for the isolation of pure radium.
When WW1 broke out Marie thought X-rays would help to locate bullets and facilitate surgery. As it was important not to move the wounded she invented X-ray vans and trained 150 female attendants.
From 1922, now a member of the Academy of Medicine, Marie devoted her time to the study of the chemistry of radioactive substances and their medical application.