The first routine application of dried blood spots (DBS) dates back to 1961, where Dr. Robert Guthrie published a unique bacterial inhibition assay for measuring phenylalanine in newborns to detect phenylketonuria (PKU). Hereby, a square absorbent filter paper was either dipped in urine or placed into a baby’s diaper, to let it soak the urine and then allowing it to dry. Only after 1961, identification circles were printed on the filter paper as a target for blood collection.
The approach of screening PKU from filter paper, which is easily transportable and inexpensive, made the application on large scale possible. Due to this new methodology, public health programs adapted and PKU analysis from DBS became a standard for Newborn Screening (NBS).
For the past 50 years, the novel and low-cost approach of blood collection introduced by Dr. Robert Guthrie has led to worldwide population screening of inherited metabolic diseases in newborns and the application has been expanded to many other fields. The initial protocol was also limited to qualitative analysis because analytical instruments did not have the required sensitivity. During the past years, a revival of the DBS technique can be observed, indicated by the number of newly reported applications. A key driver of this trend was the development and application of tandem mass spectrometry, which enabled far more sensitive analysis.
for further information, see Siegried A. Centerwall, Willard R. Centerwall, The Discovery of Phenylketonuria: The Story of a Young Couple, Two Retarded Children, and a Scientist, Pediatrics, Vol 105, Is. 1, 2000