Calibration, Validation, Qualification and System Suitability Tests in the Electrochemistry

Calibration, Validation, Qualification Calibration, Validation, Qualification and System Suitability Tests in the and System Suitability Tests in the

ElectrochemistryElectrochemistry

Ghazanfar Abbas

ContentContent

Introduction, Definitions Validation of the dosing unit (Dosing-

Test) Validation of a titrating system Validation of a coulometer Summary

CalibrationCalibration

Determination of the function between the measuring value and the result.

Kalibration

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ValidationValidation

Error calculations in a analysing system using chemical, physical and mathematical basics.

Important points:

linearity, selectivity,

correctness, accuracy

QualificationQualification

Validation to check general quality characteristics of a measuring system compared to the technical specifications.

System Suitability TestsSystem Suitability Tests

Test of an instrument or a method for the analysis of a certain sample.

Validation of the dosing unitValidation of the dosing unit

Dosimat test according to AB 238

Validation of the dosing unitValidation of the dosing unit

Realization:

Dose 10 different volumes between 0.1 und 1 cylinder into a bottle on an analytical balance.

accidently sequence

accidently volumes (except 0.1 and 1 cylinder)

Validation of the dosing unitValidation of the dosing unit

Importent points:

Density must be known on a constant temperature (no sunbeam, no draught or wind)

The Burette tip has to be fixed above the balance no micro-valve can be used. The air in the balance should be saturated with the

solvent used, to get a stable reading.

Validation of the dosing unitValidation of the dosing unit

Calculation

Vreal = mread * 1 / rF * ( 1 + rL / rF - rL / rS )

Vreal : real volume in ml, calculated from the weighing result

mabgel. : mass reading from the balance

rF : density of the dosed solution

rL : density of the air in g/ml

rS : density of the standard used for the calibration of the balance

Validation of the dosing unitValidation of the dosing unit

Evaluation (using statistics)

rel. error : difference real volume to read volume

linear regression: correlation, slope, y-axis

trendline Vreal/Vread

Validation protocolValidation protocol

Validation protocolValidation protocol

Opinion and ConclusionOpinion and Conclusion

Metrodata "Dosing-Test"Metrodata "Dosing-Test"

It is possible to automate this procedure

Therefore the windows software

Metrodata "Dosing-Test" (6.6025.000) is necessary.

Additionally the cables: - balance - pc

- dosing unit - pc

Metrodata "Dosing-Test"Metrodata "Dosing-Test"

Validation of a Titration SystemValidation of a Titration System

Titrator test according to AB 252 (KF AB 255)

Validation of a Titration SystemValidation of a Titration System

Realization:

10 Titrations with the same parameters but different sample sizes are done.

The consumtion has to be withinl 0.2 - 0.9 cylinder volumes.

Sample : Titer substance or Standardsample

Validation of a Titration SystemValidation of a Titration System

Important points:

Constant temparature (no sunbeam, no draught or wind)

Electrode and burette tip in correct positions Electrode condition (electrode test necessary ?) correct sample size (balance and cylinder)

Validation of a Titration SystemValidation of a Titration System

Evaluation using statistics

Standarddeviation: (Results)

linear regression: correlation, slope, y-axis

trendline titer / consumption

Opinion and ConclusionOpinion and Conclusion

Are all the values and parameters within the limits?

Yes ----- The system is o.k. for a certain periode !

No ------ Additional checks are necessary, -------------------------- error search!!

Opinion and ConclusionOpinion and Conclusion

Error search :

Repeat the validation, maybe an other user Check the different components

(balance, measuring unit, electrode, dosing unit) Titration parameters, mode, calculation

Validation of a KF TitratorValidation of a KF Titrator

The validation of KF titrator is simular to a normal Titration system.

Different standards can be used:

- Certified standards

- Defined samples

- Water (ul Syringe)

Validation of a KF CoulometerValidation of a KF Coulometer

For the coulometeric water determination, no dosing unit is used.

The method normally works for samples containing 0.05 to 10 mg water

The validation should be done for the range which is used for real samples in the certain laboratory.

(e.g. 0.2 to 2 mg or 0.05 to 0.5 mg with the limits for this range)

Validation of a KF CoulometerValidation of a KF Coulometer

Important points:

dry cell tightness of the cell ( drift below 20 ug/min.) new reagent handling of the standard (rinse the syringe) clean electrodes

SummarySummaryA Validation can be separated into different steps:

preparation

realization -- according to the instruction

evaluation -- using statistics

Opinion and conclusion -- ok or error search

SummarySummary

Experience from the validation should influence the daily routine !

Experience from the daily routine should influence the instructions for a validation and also the periode for the validations!

Support from MetrohmSupport from Metrohm Metrohm is ISO 9000 certified Selftest of the instrument on start up. Diagnosis in the instructions for use Different application bulletins (238, 252, 255) pH- electrode test in the pH-Meter 713 and 692 Metrodata "Dosing-Test" Software "GLP- page" in the 726 Titroprocessor Certified buffers und electrodes Seminars for customers, sales and service

people CH Service contracts

DiscussionDiscussion

Do you have additional wishes from Metrohm?