He joined the Hygienic Laboratory of the United States Public Health Service in 1928, which merged with the National Cancer Institute in 1937, where Earle worked the remainder of his life.
[1][2][3] Earle published or co-published more than one hundred scientific articles.
He significantly contributed to the technology of the growth of cells in vitro.
[5][6] He formulated Earle's salts,[4] an isotonic saline solution (or balanced salt solution) with glucose and bicarbonate, which constitutes the base of many cell culture media.
[7] Culture of Animal Cells: A Manual of Basic Technique and Specialized Applications, Sixth Edition [8] Animal-cell culture media: History, characteristics, and current issues [9]