SOP for calibration of micropipette is described in this post which you can follow in the section of microbiological lab.

Objective:

This procedure has been established for calibration of micropipette.

Scope:   

This procedure is applicable to sterile manufacturing area and microbiology lab.

Responsibility:                          

Microbiologist.                             

Accountability:

Quality Control Manager.            

Procedure:

The volume to be dispensed or taken will be changed by rotating the ring.

Attach the pipette tips firmly and immerse it approximately 3-5mm into the  liquid. 

Press the control button to slide back slowly and pull the tip out.

Hold the tip and press down the liquid slowly again press the button until the tip is completely empty.

Calibration: 

the area/surface where calibration is being performed must be vibration free.

To calibrate the micropipette the temperature of water must be maintained between 20-25°C. 

To calibrate the micropipette first of all find out the density of water and then set the desired volume with the help of volume-setting knob. 

Carefully pick the tip and rinse with distilled water by pipetting the adjusted volume at least 3–4 times. 

Carefully pipette out distilled water into a tarred volumetric flask take the readings atleast for  ten times and record the result. 

Calculate the pipetted volume as per formula:

Volume = Weight of water

        Specific gravity of water

 Formula for %variation:

% variation = 100 x (actual weight-observed weight)

                          Specific gravity of water  

Precautions:

 Use of analytical balance with a precision of 0.1 mg is mandatory

Frequency: Quarterly