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Updated: Feb 4, 2026

Direct Detection of Isolevuglandins in Tissues Using a D11 scFv-Alkaline Phosphatase Fusion Protein and Immunofluorescence
Published on: July 5, 2021
Detection of Alkaline Phosphatase Enzyme Activity with a CatalyCEST MRI Biosensor
Iman Daryaei1, Mahsa Mohammadebrahim Ghaffari1, Kyle M Jones2
1Biological Chemistry Program, Department of Chemistry and Biochemistry, University of Arizona, Tucson, Arizona 85719, United States.
Abstract:
Responsive CEST MRI biosensors offer good sensitivity and excellent specificity for detection of biomarkers with great potential for clinical translation. We report the application of fosfosal, a phosphorylated form of salicylic acid, for the detection of alkaline phosphatase (AP) enzyme. We detected conversion of fosfosal to salicylic acid in the presence of the enzyme by CEST MRI. Importantly the technique was able to detect AP enzyme expressed in cells in the presence of other cell components, which improves specificity. Various isoforms of the enzyme showed different Michaelis-Menten kinetics and yet these kinetics studies indicated very efficient catalytic rates. Our results with the fosfosal biosensor encourage further in vivo studies.
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