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Detection of Alkaline Phosphatase Enzyme Activity with a CatalyCEST MRI Biosensor.

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.

SUBMITTER: Daryaei I

PROVIDER: S-EPMC6145488 | biostudies-literature | 2016 Jul

REPOSITORIES: biostudies-literature

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Detection of Alkaline Phosphatase Enzyme Activity with a CatalyCEST MRI Biosensor.

Daryaei Iman I Ghaffari Mahsa Mohammadebrahim MM Jones Kyle M KM Pagel Mark D MD

ACS sensors 20160621 7

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 ...[more]

PMID: 30246144

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