SOP for Calibration of Metrohm Potentiometer

OBJECTIVE 

To lay down the procedure for calibrating the MetrohmPotentiometer. 

SCOPE 

This SOP applies to the Calibration of the Potentiometer being used in the Quality Control Laboratory at Pharmainfo Ltd.

RESPONSIBILITY 

It is the responsibility of the QC Executive assigned to carry out the calibration procedure fully without deviation. 
It is the responsibility of the Manager QC to enforce the procedure. 

ALSO READ: SOP for Calibration of Malvern Particle Size Analyzer

PROCEDURE 

Frequency: Once in 6 months. 

• Operate the instrument as per the current version of SOP for the operation of the Potentiometer.

Electrode Calibration 

• Select the method pH 
• Clean the pH electrode with water every time before every operation 
• Keep the electrode in pH 4.01 buffer and record the pH in Attachment-I
• Repeat the procedure with pH buffer solutions 7.0 and 10.0.

Burette Calibration 

• Fill the bottle with purified water.
• Select the added volume of 10ml from the instrument and press the ‘START’ key. 
• Collect the water in a previously weighed beaker and take the weight, record the results in Attachment-I. 
• Repeat the above steps by taking add volumes 20ml, 30ml, 40ml & 50ml 

Linearity 

• Select the method for calibration from the instrument 
• Take 5 different accurate weights of potassium Hydrogen phthalate (100mg, 150mg, 200mg, 250mg, and 300mg) in a 250ml beaker and dissolve in 100ml water 
• Perform titration using standardized 0.1M Sodium Hydroxide 
• After completion of the titration take the printouts of the results 
• Calculate the correlation coefficient and record the results in Attachment-I.

ATTACHMENTS 

Calibration report of Potentiometer

REVISION HISTORY 

Nil

ALSO READ: SOP for Operation of Potentiometer (Metrohm)