Testing of Four Home Phenylalanine Monitoring Prototype Devices

A real time, point-of-care and home phenylalanine monitoring system would provide patients
with quick results and feedback. Home monitoring devices' phenylalanine measurements will be
compared to the current gold-standard measurement of phenylalanine (plasma concentration) in
four subjects with PKU and one control subject. The study will enroll subjects with
different baseline phenylalanine concentrations (i.e., patients with poor to good metabolic
control, assessed by comparing current phenylalanine concentrations to established treatment
ranges).

For each prototype device, three separate measurements of phenylalanine per subject will be
performed. Three prototype devices require whole blood, thus 1 teaspoon (approximately 4mL)
of whole blood will be collected through venipuncture and blood spots will be used to
conduct tests. One prototype requires capillary blood to be collected through a fingerstick,
and will require three blood spots from the stick. A single plasma amino acid analysis for
each participant will also be performed using leftover whole blood from the 4mL blood draw
through quantitative ion exchange chromatography, reported as micromoles/L.

Inclusion Criteria:

- diagnosis of PKU or hyperphenylalaninemia (PKU group)

- any age

- in good health (PKU and control group)

Exclusion Criteria:

- pregnant

- have any medical comorbidities

- considered unfit for participation by the principal investigator