The pipette is an instrument commonly used in biological and chemical laboratories to remove trace amounts of liquid. Its advantages are easy operation and high accuracy. With it, laboratory pipetting is no longer the main cause of analysis errors.
 
For so-called precision instruments, most of the time, it is necessary to carefully introduce the profound principles, but the principle of pipettes is very simple, that is, the piston moves up and down through the elastic force of the spring to discharge or absorb liquid.
 
Generally speaking, there are two types of pipettes, one is the air displacement type, and the other is the external piston type, which is often used as a special pipette and has a relatively narrow application range. This type of pipette can be used to pipette high-viscosity samples.
 
The so-called air displacement type is to press down the piston to press out the air inside the lower end of the pipette, and then when the piston is moved up, the air pressure inside the lower end of the pipette is lower than the external air pressure, so that it can suck up the liquid under the action of external air pressure. In short, the air goes out and the liquid comes in.
 
The so-called external piston type is actually exactly the same as the principle of the syringe. After seeing the working process of the syringe, you can probably understand the principle of the external piston type.
 
In addition, it is usually divided into single channel and multiple channels according to the number of channels. From the first pipette to the mainstream of the pipette market, it is a pipette that can only transfer one liquid sample at a time. We call it a single-channel pipette. However, with the rapid development of life sciences, single-channel pipettes often cannot fully meet the needs. As a result, a multi-channel pipette appears, which can transfer multiple liquid samples in one pipetting operation. This type of pipette is commonly known as a "discharge gun".