Pipette and suction head is a complete system, only from the same manufacturer to ensure the accuracy and precision of the results, in the calibration and daily use of pipette must choose the matching manufacturer of suction head. Install the suction head by using the micro-rotating mounting method. Insert the pipette nozzle vertically into the suction head and gently press it tightly by rotating it in a small amplitude. Do not knock up and down or shake around to avoid the deformation of the suction head and the wear of the nozzle under strong friction. Some micro pipettes have thin nozzle, so hard knocking may damage the nozzle.

The tightness of pipette directly affects the accuracy of the result. After ensuring that the pipette uses the matching suction head of the same manufacturer and the suction head is tightened, simple visual method can be used to detect the air tightness of the pipette. For a pipette less than 200ul, dip the suction tip into the liquid level (1-2) mm and wait for 20 seconds to check whether the liquid level in the suction tip drops. If it does, the pipette leaks. If the pipette is larger than 1000ul, place it vertically for 20 seconds after suction, and observe whether there is liquid dripping at the tip of the suction head. If there is, the pipette leakage phenomenon exists.

The types of pipettes are becoming more and more diverse. Experimental personnel should choose the appropriate calibration point and electronic balance standard according to different types of pipettes, use the pipette nozzle of the same manufacturer and correct pipette operation, and calibrate the pipette capacity regularly to ensure the accuracy and consistency of its capacity. When the indicating value of the pipette is out of tolerance, it should first check whether the tightness of the pipette is normal, and then judge whether it can be calibrated in the laboratory by itself. After calibration, the measurement method should be used again for calibration.