Mr. Zaffaroni, a native of Montevideo, Uruguay, earned a bachelor's degree from the University of Montevideo in 1941. He first came to the United States on a Fulbright Scholarship to the University of Rochester, where he earned a doctorate in biochemistry in 1949.
In 1951, he joined Syntex Corp., a small chemical company in Mexico that was prominent in steroid research. He played a key role in transforming it into a major pharmaceutical company headquartered in the United States in the Stanford Research Park. Eventually, he became president of Syntex Laboratories and president of Syntex Research Institute.
He was widely considered a pioneer in drug delivery and the field of biotechnology.
Mr. Zaffaroni founded a number of companies, including ALZA Corp. (an acronym of his name), which was acquired by Johnson & Johnson in 2001; Affymax Inc., which was acquired by Glaxo in 1995; Affymetrix, Alexza Pharmaceuticals, Symyx Technologies and Maxygen.
In 1980, he cofounded the DNAX Institute of Molecular and Cellular Biology with three Stanford scientists: the late Arthur Kornberg, professor of biochemistry and winner of the Nobel Prize in 1959 for his work elucidating how DNA is built; Paul Berg, the Robert W. and Vivian K. Cahill professor of cancer research, emeritus, and winner of the Nobel Prize in chemistry in 1980 for his fundamental studies of the biochemistry of nucleic acids with particular regard to recombinant DNA; and Charles Yanofsky, Morris Herzstein professor of biology, emeritus.
The DNAX Institute, which supported the development of novel therapeutic products based on recombinant DNA technology, was sold to Schering-Plough Pharmaceuticals in 1982.
In 1995, President Bill Clinton presented Mr. Zaffaroni with the National Medal of Technology, the nation's highest honor for individual achievement in science and technology.
In 2006, Stanford established a $10 million financial aid program for Latin American students at Stanford to honor Mr. Zaffaroni and his wife, Lida. The Alejandro and Lida Zaffaroni Scholarship and Fellowship Program was partly funded by gifts from a group of more than 35 associates who credited Mr. Zaffaroni with providing inspiration, mentorship and friendship during their careers.
The Zaffaronis were also major donors to the Lida and Alejandro Zaffaroni Breast Imaging Center at the Stanford Cancer Center.
Mr. Zaffaroni also served as a member of the Stanford University Hospital Board of Directors and the Beckman Center for Molecular and Genetic Medicine Advisory Council at Stanford.
He is survived by his wife, Lida, his son Alejandro and daughter-in-law Leah, his daughter Elisa, and two grandchildren, Alejandro Peter and Charles A. Zaffaroni.
A private family service has been held. A memorial service may be held at a later date