Northrop grew up in New York state. She received her A.B. degree, cum laude, from Syracuse University in 1965 and received her M.L.S. degree from Rutgers University in 1966. She received her MB.A degree in finance from The Wharton School of the University of Pennsylvania in 1976. Mary Elllen was a reference librarian at the University of Iowa and Douglass College of Rutgers University, and a supervisor of the technical services department at Plainfield (NJ) Public Library. She was a budget analyst at the Erie. PA General Electric Company and a financial analyst and income tax analyst at the DuPont Company. She was a member of the Phi Kappa Phi and Pi Mu Epsilon national honorary societies. She loved music and she left behind an amazing gift for the Music School of Delaware. She had never donated to the Music School of Delaware before, but she left the biggest gift in the nearly 100-year-old school’s history. She left the school $10 million in her will. She died in June 2021. She was predeceased by her father, Howard Schuyler Northrop, and her mother, Ethel Barden Northrop. She is survived by several cousins.