INTENDED USE
For the quantitative in vitro determination of Potassium in human
serum.
PRINCIPLE OF THE METHOD
Potassium is determined spectrophotometrically through a kinetic
coupling assay system using potassium dependent pyruvate kinase2-3.
Pyruvate generated is converted to lactate accompanying conversion
of NADH analog to NAD analog. The corresponding decrease of optical
density at 380 nm is proportional to the potassium concentration in the
serum.
CLINICAL SIGNIFICANCE
Measurements obtained by this device are used to monitor electrolyte
balance in the diagnosis and treatment of diseases conditions
characterized by low or high blood potassium levels. In healthy
individuals, an extracellular fluid level of potassium is regulated to
maintain at 3,5 – 5,1 mmol/L1.
Small deviations from normal levels can
have severe health consequences. Monitoring serum potassium
concentration is important in both routine checks and emergency
rooms.
CALIBRATION
This assay should be calibrated using the enclosed L and H standards.
Potassium concentration in sample is determined from the calibration
curve using the included L & H potassium standards.
STORAGE AND STABILITY
All the components of the kit are stable until the expiration date on the
label when stored tightly closed at 2-8ºC, protected from light and
contaminations prevented during their use.
Do not freeze. Do not use reagents over the expiration date.
ADDITIONAL EQUIPMENT
- Spectrophotometer or colorimeter measuring at 380-405 nm.
- Thermostatic bath at 37ºC (± 0,1ºC)
- Matched cuvettes 1,0 cm light path.
- General laboratory equipment (Note 1).
SAMPLES
This assay is formulated for use with non-hemolysed serum. No special
handling or pretreatment is needed.
Serum samples should be collected such that testing is performed as
soon as possible and within 5 days after the specimen collection.
NOTES
1. In order to avoid contamination it is recommended to use disposable
material.
2. Use clean disposable pipette tips for its dispensation.
3. SPINREACT has instruction sheets for several automatic
analyzers. Instructions for many of them are available on request.
