Karle’s husband, Jerome Karle, who passed in 2013 at age 94, had developed the technique of X-ray crystallography in the 1950s. This is based on analyzing the patterns of light that bounce off a crystallized molecule. It remains the most widely used method for determining the three-dimensional structure of molecules.
Jerome Karle received the Nobel Prize in Chemistry along with Herbert Hauptman in 1985. Isabella Karle played a big role in his work by demonstrating how the technique could be used.
She had used it to explore the structures of biological molecules found in drugs, steroids, and frog toxins. Karle told The New York Times in 2013, “After I found some structures that no one could have dreamt of solving before, it started to get a lot of attention.”
Karle was born in Detroit in 1921 to Polish immigrants. From an early age, she was inspired to pursue chemistry by a female high school chemistry teacher as well as a biography of Marie Curie, a Nobel Prize-winning physicist also of Polish origin. She went on to pursue bachelor’s, masters, and doctoral degrees, which she accomplished before the age of 23.
Along with her husband, Karle had worked on the Manhattan Project, the research program during World War II that led to the development of the first nuclear weapons. They later moved to the U.S. Naval Research Laboratory in Washington D.C. and started their work on crystallography. Upon receiving the Nobel, Jerome Karle had told The Los Angeles Times that his wife also deserved the prize: “I can’t think of anyone who is more qualified than my wife.”
The cause of death had been a brain tumor, according to The Washington Post. Karle is survived by her daughters Louise Karle Hanson, Jean Karle Dean, and Madeleine Karle Tawney–who are all scientists–four grandchildren, and a great-granddaughter.