Thermo Scientific 981197 Guia De Inicio Rapido

Page 1 D01768_05_insert_pH(ISE)_MU
EN
pH Electrode
981197
INTENDED USE
For in vitro use. For measurement of pH to calculate ionized calcium at pH 7.4 on
Microlyte and Optima analyzers.
All test results must be interpreted with regard to the clinical context.
SUMMARY (1)
The binding of calcium by protein and small anions is influenced by pH in vitro and in vivo.
Decreasing pH in vitro decreases ionization and negative charge, decreasing protein-
bound calcium and increasing free calcium. The concentration of free calcium changes by
about 5% for each 0.1 – unit change in pH.
PRINCIPLE OF THE PROCEDURE
Electrolyte measurements are made with ion selective electrodes (ISE) directly without any
dilution of the sample. The measurement cell consists of several ion selective electrodes
and one reference electrode. The measured potential between each ISE and the common
reference electrode is in the simplest case related to the natural logarithm of the ionic
activity according to Nernst equation (6). The changes in potential are developed across
the ISE membrane/ sample interface
PRODUCT INFORMATION
The pH electrode is packed in a foil bag and the electrode is coded with a white dot.
Precautions
For in vitro diagnostic use only. Exercise the normal precautions required for handling all
laboratory reagents.
Do not remove the electrode pin.
The electrode is maintenance free and has been filled during the manufacturing process
and there is no need for refilling the electrode.
There must always be a small O-ring between two electrodes.
When removing an electrode block from the instrument, detach it from the end slices and
leave them intact.
Preparation
The electrode is ready for use and doesn't require activation or filling.
In order to install the electrode proceed as follows
1) Remove the foil bag from the electrode box and tear it at the cut to open.
2) Check that the inner filling solution is covering the glass tube.
3) If there are air bubbles hold the electrode upright and gently force out any trapped
air from the membrane surface with a flick of the wrist. (Don't tap the electrode on a
hard surface)
4) The electrode is now ready to be installed according to the electrode order per the
instrument User Manual or the instrument.
5) Fill in the installation sheet
6) Run cleansing solution and serum based samples through the instrument in the
normal fashion immediately after installation of the electrodes prior to calibration.
7) Perform the calibration.
Storage and Stability
Regular use of washing solution e.g. Washing solution, code 980302 and e.g. Cleansing
solution, code 980659, is essential for electrode performance.
See the last possible installation date on the electrode package label (install before). The
warranty is valid for 6 months from the installation date.
Electrodes must be stored at 2...8 °C before installation.
SPECIMEN COLLECTION
Sample Type
Serum or heparin plasma can be used.
Precautions
Human samples should be handled and disposed of as if they were potentially infectious.
Check that there are no bubbles in the sample cups or on the surface of samples when
inserting cups into the Optima analyzer
Storage (2)
The sample can be stored for 2 h at 4...8 °C. The sample has to be kept in well-closed
tube.
TEST PROCEDURE
Refer to the User Manual and Application Notes for an automated procedure on your
analyzer. Any application, which has not been validated by Thermo Fisher Scientific Oy
cannot be performance guaranteed and therefore must be evaluated by the user.
Materials provided
The pH electrode as described above.
Materials required but not provided
ISE standard solutions, controls, reference electrode kit, reference electrode solution, calcium
electrode, washing solution and cleansing solution as indicated below.
Calibration
Use ISE Standard Solution 1, code 980883 and ISE Standard Solution 2, code 980884
and ISE Standard Solution 3, code 980885 or
ISE Calibrators 2 & 3 for Optima, code 981791 according to the instructions given for your
analyzer.
Note: Check that there are no bubbles in the calibration cups or on the surface of
calibrators when inserting cups into the Optima analyzer.
In Optima it is recommended that the instrument be calibrated at least once a month and
in all analysers always when electrodes have been replaced, every time a new lot of ISE
Standard Solution is used or whenever control results require recalibration.
Traceability:
Refer to the package insert of ISE Standard Solutions 1, 2 and 3.
Quality Control
Use quality control samples at least once per day, after each calibration and every time a
new bottle or bag of ISE Standard Solution 1, 2 or 3 is used. It is recommended to use two
control levels.
Available controls:
Select Ion Low, code: 981059
Select Ion Normal, code: 981058
Select Ion High, code: 981094
The control intervals and limits must be adapted to the individual laboratory requirements.
The results of the quality control sample(s) should fall within the limits pre-set by the
laboratory.
Reference Electrode Kit, code 980845
Reference Electrode solution, code 980314
2+
Calcium (Ca ) Electrode, code 981195
Washing solution 1 % , code 980302
Cleansing solution, code 980659
CALCULATION OF RESULTS
The results are calculated automatically by the analyzer.
LIMITATIONS OF THE PROCEDURE
Measured pH can only be used to calculate ionized calcium consentration at pH 7.4.
MEASURING RANGE
6 - 8.5
PERFORMANCE CHARACTERISTICS
Imprecision
Within run Mean 7.86
SD
0.012
n 20
Unit to unit Mean 7.82
SD
0.050
n 40
BIBLIOGRAPHY
1. Burtis, CA and Ashwood, E R (ed.), Tietz Fundamentals of Clinical Chemistry, 5th
edition, W B Saunders Company, Philadelphia, 2001, pp. 801.
2. Guder WG, Narayanan S, Wisser H, Zawta B. List of Analytes; Preanalytical
variables. Brochure in: Samples: From Patient to the Laboratory. GIT Verlag GmbH,
Darmstadt, 1996.
3. Heins, M., Heil, W. and Withold, W., Storage of serum or whole blood samples?
Effects of time and temperature on 22 serum analytes., Eur. J. Clin. Biochem. (33)
1995 221 – 228.
4. Rahn, H., Reeves, R. B. and Howell, B. J., Hydrogen ion regulation, temperature
and evolution., Am. Rev. Respir. Dis. 112 (1975) 165 - 172.
5. Maas, A. H. J., Kofstad, J., Siggaard-Andersen, O., et al., Eds., Physiology and
methodology of blood gases and pH., Vol 4., Proceedings of the 9th meeting of the
IFCC expert panel on pH and blood gases, IFCC Workshop, Oslo 1983,
Copenhagen, Private Press, 1984.
6. Cammann, Karl, Working with Ion-Selective Electrodes Chemical Laboratory
Practise, Second Edition, Springer-Verlag, Berlin Heidelberg New York 1979.
MANUFACTURER
Thermo Fisher Scientific Oy
Clinical Diagnostics Finland
Ratastie 2, P.O. Box 100, FI-01621 Vantaa, Finland
Tel. +358 9 329 100, Fax +358 9 3291 0300
www.thermo.com/konelab
Date of revision (yyyy-mm-dd)
2007-08-29
Changes from previous version
Company name updated.
Mean 8.23
CV% SD CV%
0.2 0.012 0.1
20
Mean 8.22
CV % SD CV %
0.64 0.015 0.18
40