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Italian CONTRIBUTI SCIENTIFICI – Scientific Papers
Volume:
Biochimica Clinica 2022; 46(1) 034-038
Pubblicato on-line:
August 8, 2021
DOI:
10.19186/BC_2021.047
Measurement of biotinidase activity using dried blood spots by a spectrophotometric assay for biotinidase activity
Assay for biotinidase activity
AUTORI
1Department of Physiology and Biochemistry, School of Medicine, The University of Jordan, Amman, Jordan
2School of Medicine, The University of Jordan, Amman, Jordan
3Department of Neurological Sciences, University of Nebraska Medical Center, Omaha, NE, USA
4Department of Pediatrics, School of Medicine, The University of Jordan, Amman, Jordan
ABSTRACT
Assay for biotinidase activity
Introduction: biotinidase is required for biotin recycling; its deficiency results in loss of this coenzyme and, hence, the function of many critical enzymes. Delay in the diagnosis of biotinidase deficiency causes irreversible neurological damage; however, it is completely reversible and treatable if detected early. The aim of this study is to measure the activity of the biotinidase enzyme in dried blood specimens using a spectrophotometric technique.
Methods: dried blood specimens were collected from adults (n=81), neonates (n=50), as well as from a patient and his two siblings. A microplate-based enzyme kinetics assay was implemented to assess enzyme stability and activity using N-biotinyl-p-aminobenzoateas as a substrate.
Results: the enzyme was found to be stable for 28 days in dried blood spots stored at -20 ºC. The assay was effective in measuring similar activities of biotinidase among healthy adults and neonates. On the other hand, no biotinidase activity was detected in the patient and low activity was measured in his two siblings.
Conclusion: the assay provides a cost-effective method for the early detection of biotinidase deficiency.