Pipette Operation And Common Mistakes
Pipette is a perfect tool to transport a measured volume of liquid. It is widely used as a media dispenser in labs. For different purposes and needs of accuracy and precision, we can find pipettes in several designs in the market, glass and polyethylene ones. Adjustable and electronic pipettes are available too.
The pipette is always needed wherever the precise transfer of liquid is required in the lab. Regardless of what type the pipette you have, you should handle them with care. Placing the pipette 1/4 of an inch from the bottom of the container is the right way to prevent damage when you draw the liquid. You’d better tap the side of the pipette to remove excess droplets very gently when the required volume of the liquid is drawn up. Always hold the pipette at a 10-20 degree angle when you dispense. Never blow through a pipette and try to remove extra liquid.
To make sure the pipettes working accurately and also to prevent pollution from previous contents, you should clean the them after use.
Operation Procedures of Pipette
To do a correct liquid operation using a normal pipette, there are some operating steps for follow, first, connect the suction head, then press the piston exhaust, insert the suction head approximately 2 mm below the liquid level, next, inhale liquid and transfer to the destination container, finally, push off the suction head. It takes about 10 seconds for the whole process.
Maintenance Procedures of Pipette
In experimental operation, when there is liquid in the suction nozzle of the pipette, do not place the it horizontally or inversely to prevent the liquid flowing into the piston chamber to corrode the pipette piston.
Besides, use the pipette correctly to absorb and drain liquid to achieve high precision; when it occurs leakage in operation, stop for one to three seconds after suction to see whether the liquid level in the suction head drops, if the liquid level drop, firstly to check whether there is a problem with the suction head, if it is, just replace the suction head, if not, call for professional maintenance personnel to repair.
Common mistakes when using pipettes
1 ×: when pipetting, the pipette itself tilts, resulting in inaccurate pipetting
√: Pipet vertically, suck slowly and release slowly
2 ×: overexert when assembling the tip, which makes the tip difficult to detach and shorten the service life of the pipette
√: take strength even when assembling the tip head, increase strength slowly
3 ×: lay the pipette with residual liquid
√: hang the pipette on the pipette holder
4 ×: use a large-scale pipette to draw small volume samples
√: select a pipette with the appropriate range to ensure that the required pipetting is within the larger reading range that the pipette can adjust.
5 ×: directly press the second gear when sucking
√: you should press directly to the first gear when aspirating
6 ×: use acetone or highly corrosive liquid to clean the pipette
√: the pipette can be wiped with a detergent such as 75% ethanol, 10% bleach or neutral soap.
7 ×: take too much strength when aspirating and draining
√: slowly release the thumb when aspirating, and then take it out after the liquid has completely entered the tip; slowly press the first gear when draining, then press the second gear.