Calibrators / Reference Solutions - Elitech FreezePoint 6000 Series User Manual

Installation, Operation, and Performance Qualification

Calibrators / Reference solutions

It should be noted that there is no generally accepted national or international reference for the traceability
of the calibration standards in the field of the freezing point osmometry. Reference solutions for the
osmometry, however, should be produced according to the national or international pharmaceutical
directives (e.g. USP, JP, PhEur, NIST, etc.).
Measuring Reliability Controls (MRC) in the field of GxP practice.
Measuring reliability controls are used to check whether the medical device is within the maximum
measuring deviation (error margin), based on the error limits, which the manufacturer has established in
the User's Manual.
Under GxP the MRC is executed by means of Standard Solutions and Procedures stipulated in
international Pharmacopoeias (such as current editions of the European Pharmacopeia, USP Monograph
<785> OSMOLALITY AND OSMOLARITY, etc.).
For example, the table below can be used to produce reference solutions to be used as measuring
reliability controls.
Reference Saline Solutions
(mOsmol/kg)
100
200
290*
300
400
500
600
700
850**
2000**
Unless otherwise noted reference solutions are based on the European Pharmacopoeia, 4th Edition.
(*) Based on Geigy Scientific Tables, 8th edition.
(**) Determined experimentally using substantially equivalent freezing point osmometer
Quality Control
ELITechGroup calibrators are avaliable for establishing high quality calibration curves for typical clinical
ranges. Upon evaluation of control values and the determination of admissible ranges appropriate
statistical methods should be used. After calibration reference measurements should be made using
solutions with known osmolality to verify the acceptance of the calibration. At least one reference material
of known osmolality should be used as control. Deviations to the expected result may be a sign for
erroneous use of the device, the calibration and reference material, for contaminated syringes or vessels or
a malfunction of the device.
Osmolality Standard Solutions
(Weight in grams of
sodium chloride per kg
3.087
6.260
9.141
9.463
12.684
15.916
19.147
22.380
27.228
63.930
Molal Osmotic
Coefficient (ϕm NaCl)
of water)
0.9463
0.9337
0.9270
0.9264
0.9215
0.9180
0.9157
0.9140
0.9122
0.9142
Freezing Point
Depression (°C) ΔT
0.186
0.372
0.539
0.558
0.744
0.930
1.116
1.302
1.579
3.716
128