The Fluorometric Estimation Of Lactoflavin

Pure, crystalline lactoflavin has been prepared from a water-soluble vitamin concentrate derived from milk. A method of estimating lactoflavin involving its fluorescent properties in “black light” is presented. The method is simple, involving only standard lactoflavin solutions and an ultraviolet light generator equipped with a suitable filter. The method was found to be accurate to 0.1γ of lactoflavin, but concentrations as low as 0.05γ/ml. of lactoflavin could be detected. The authors acknowledge the cooperation of the Phototechnical Department of the Agfa Ansco Corporation, Binghamton, New York; The National Carbon Company, Cleveland, Ohio and The Caxton Company, Cleveland, Ohio. The assistance of Dr. B. L. Herrington, temporarily employed by The Dry Milk Research Laboratories, is also gratefully acknowledged.