Validation

The design of the Metrohm antidiffusion tips with the antidiffusion valve enables very accurate
dosing. The principle is a ‘pressure valve’ which opens synchronously with the movement of the Dosing Unit piston (i.e. when the pressure in the tubing increases) and closes when the pressure in the tubing drops. This principle ensures that the volume flow stops abruptly when piston movement stops and no drop formation or titrant leakage occurs subsequently.
If this mechanism is not working properly then a volume different from that documented can leak from the antidiffusion tip after the dosing step. This ‘leakage’ may also cause a delayed stabilization of the measured signal and produce faulty and inaccurate results.
Metrohm recommends the use of the titrimetric volume test method described below as the Standard Operating Procedure for validating Metrohm antidiffusion tips (6.1543.200, 6.1543.130 & 6.1543.140, each with 62726.090 Antidiffusion valve).
This titrimetric volume test can be used for the following purposes:

• Quality assurance by the manufacturer
  
• Quality assurance of analytical or other measuring systems by the user
  

The described method is not an official reference method.

Among other things, GLP (Good Laboratory Practice) requires that the accuracy and precision of analytical
instruments are checked at regular intervals using Standard Operating Procedures (SOPs).

Metrohm recommends the use of the gravimetric test method described below as the Standard Operating
Procedure for validating Dosing and Exchange Units.
This gravimetric linearity test can be used for the following purposes:
• Quality assurance by the manufacturer
• Quality assurance of analytical or other measuring systems by the user

The described method is not an official reference method. The metrological requirements placed on piston burets, in particular the maximum permissible measurement errors, are specified in the ISO Standards 8655-1 to 8655-6.

GLP (Good Laboratory Practice) requires, among other things, the regular checking of the accuracy and precision of analytical instruments by using standard operating procedures (= SOPs).

The user is recommended to validate Metrohm instruments as a whole integral measuring system, i.e. to carry out a series of determinations with certified standards and to critically assess the results by statistical means.

Checking the electronic components of measuring instruments can and ought to be carried out in the context of regular service work by technical specialists from the manufacturing company. All Metrohm instruments are provided with start-up test routines that check that the relevant components are functioning properly when the instrument is switched on. If this produces no error message then it can be assumed that the instrument is functioning perfectly. Metrohm also supplies its instruments with built-in diagnosis programs that, if faults or malfunctions should occur, permit the user to check the functioning of particular assemblies and localize the fault. These diagnosis programs can also be included in a validation method.

As a guideline for drawing up a standard operating procedure for checking the complete analytical system, Metrohm recommends the procedure described in this Bulletin. The limiting values mentioned should be regarded as being proposals. Depending on your company-specific requirements for the accuracy of the measuring system these limits may need to be redefined in the standard operating procedures.

GLP (Good Laboratory Practice) requires periodic checking of the reproducibility and accuracy of analytical instruments by using Standard Operating Procedures (SOPs).

This Application Bulletin is intended to provide you with a guideline for the validation of your Rancimat. A standard operating procedure is proposed which allows all the Rancimat functions which are relevant for the measurement to be checked. The limits given are to be taken as being examples of what can be achieved under normal laboratory conditions. Depending on the demands placed upon the accuracy of the measuring system, it may be necessary to redefine these limits in the standard operating procedure. If very careful work is carried out under appropriate conditions then it may be possible to achieve lower limits.

The operating software for the 743 Rancimat contains prepared GLP tests for the temperature, conductivity and gas flow measurements. The operator can determine whether and which tests are to be carried out, in addition the interval between the tests and the required accuracy can also be defined. If the GLP function is activated then a comment will be made on each result report as to whether the GLP test requirements have been fulfilled. In order to be able to carry out the most important tests Metrohm offers the 6.5616.000 GLP Test Set as an option.

Further information about the topics of QA, GLP and validation can also be found in the brochure Quality management with Metrohm, which is available from your local Metrohm agency.

GLP (Good Laboratory Practice) requirements include the periodic check of analytical instruments for reproducibility and accuracy using standard operating procedures (SOP).

The user is advised to validate the Metrohm VA instruments as a complete, integrated voltammetry system, i.e. to perform a voltammetric determination using standard solutions of known content and critically assess the results using statistical methods.

Checking of the electronic and mechanical components of measuring instruments can and should be undertaken by qualified personnel of the manufacturing company as part of regular servicing. All Metrohm instruments are provided with start-up test routines. Each time the instrument is switched on, these test routines check whether the relevant assemblies are working correctly. If no error message is displayed, it can be assumed that the instrument is functioning faultlessly. Metrohm instruments are also supplied with built-in diagnostic programs, which enable the user to check the functioning of certain components in the event of malfunctions or erratic behaviour and to localize the fault. Diagnostic programs may also be integrated in a validation procedure.

The procedure described below is meant as a guideline for the preparation of standard operating procedures for checking a voltammetry system comprising the VA instrument and possibly a dispensing unit or an Autosampler. The limiting values specified must be considered as recommendations. Specific limiting values must be defined in the particular standard operating procedure taking into account in-house requirements concerning the accuracy of the analysis system.

Among other things, GLP (Good Laboratory Practice) requires that the accuracy and precision of analytical instruments are checked at regular intervals using Standard Operating Procedures (SOPs).

The user is advised to validate the pH meter as a whole integrated measuring system, i.e. including the electrode(s) and any stirrer that may be used.

The checking of the electronic and mechanical components can and should be carried out by qualified personnel from the manufacturing company as part of regular servicing. All newer Metrohm pH meters are provided with start-up test routines, which check that the instrument is functioning perfectly when it is switched on. If no error message is displayed it can be assumed that the instrument is functioning correctly. Metrohm also supplies its instruments with integrated diagnostic programs, which enable the user to check the functioning of certain components in the event of malfunctions or erratic behavior and to localize the fault. These diagnostic programs can also be included in a validation procedure.

The procedure described below is meant as a guideline for setting up a Standard Operating Procedure to check your pH meter (with electrode connected). The limits specified should be regarded as examples. Depending on the requirements placed on the accuracy of the measuring system these limits may have to be redefined in the Standard Operating Procedure.

GLP (Good Laboratory Practice) requirements include the periodic checking of analytical instruments for reproducibility and accuracy using standard operating procedures (SOP).

The user is advised to validate the Metrohm titrators as a complete, integrated titration system, i.e. to perform a series of titrations using standard titrimetric substances (primary standards) and critically assess the results using statistical methods.

Checking the electronic and mechanical components of measuring instruments can and should be undertaken by qualified personnel of the manufacturing company as part of regular servicing. All Metrohm instruments are provided with start-up test routines which check that the relevant assemblies are working perfectly when the instrument is switched on. If no error message is displayed, it can be assumed that the instrument is functioning faultlessly. Metrohm instruments are also supplied with built-in diagnostic programs that enable the user to check the functioning of certain components in the event of malfunctions or erratic behavior and to localize the fault. Diagnostic programs may also be integrated in a validation procedure.

As a guideline for the preparation of Standard Operating Procedures to check a titration system comprising a titrator, dispensing unit, measuring chain and possibly a sample changer, Metrohm suggests the procedure described in this Bulletin. The limiting values specified must be considered as recommendations. Specific limiting values must be defined in the particular Standard Operating Procedure regarding in-house requirements concerning the demanded accuracy of the measurement system.