A spectrophotofluorometer is a complex instrument that measures the spectrum of fluorescent light reflected from a substance of interest. Robert L. Bowman and Sidney Udenfriend, a physician and a biochemist working at the National Heart Institute in the early 1950s, designed and tested the form. They then worked with Hugh King Howerton, an American Instrument Company physicist, to develop the instrument that was put on the market in 1956.
The inscriptions on this example read: “American Instrument Co., Aminco, Silver Spring Maryland No. D223-62155 Serial...” and “Aminco-Bowman Spectrophotofluorimeter / American Instrument Company, Inc. / Silver Spring, Maryland, U.S.A. / Made in U.S.A. accordance with Patent Nos. 2,971.429 and 3,092,722.”
Ref: H. K. Howerton, “Spectro-Fluorescence Measuring Instrument,” U.S. Patent 2,971,429 (Feb. 1, 1961), assigned to American Instrument Company, Inc.
H. K. Howerton, “Spectro-Fluorescence Measuring Instrument,” U.S. Patent 3,092,722 (June 4, 1963), assigned to American Instrument Company, Inc.
Sidney Udenfriend, “Development of the spectrophotofluorometer and its commercialization,” Protein Science 4 (1995): 542-551.
Currently not on view
Object Name
date made
American Instrument Company
place made
United States: Maryland, Silver Spring
overall: 45.1 cm x 70.3 cm x 44 cm; 17 3/4 in x 27 11/16 in x 17 5/16 in
overall: 53 in x 39 in x 89 in; 134.62 cm x 99.06 cm x 226.06 cm
ID Number
catalog number
accession number
Credit Line
Transfer from NIH
Science & Scientific Instruments
See more items in
Medicine and Science: Chemistry
Data Source
National Museum of American History
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