What Is Pipette

Introduction

The pipette, also known as the pipette gun, is a device used to quantitatively transfer liquid. When conducting research on analysis and testing, pipettes are generally used to remove small or trace amounts of liquid. According to the principle, pipettes can be divided into air-displacement pipette and positive-displacement pipette. Gas piston pipettes are mainly used for standard pipetting, and external piston pipettes are mainly used for handling special liquids such as volatile, corrosive and viscous.

Method of pipetting

Before pipetting, make sure that the pipette, pipette tip, and liquid are at the same temperature. When sucking liquid, keep the pipette upright and insert the pipette tip 2-3 mm below the liquid surface. Before sucking the liquid, you can suck and put the liquid several times to wet the suction nozzle (especially when sucking the liquid with viscosity or density different from water). At this time, two pipetting methods can be adopted.

One is the forward pipetting method. Press the button with your thumb to the first stop, then slowly release the button to return to the origin. Then press the button to the first stop to discharge the liquid, pause for a while and continue to press the button to the second stop to blow out the remaining liquid. Finally release the button.

The second is the reverse pipetting method. This method is generally used to transfer high-viscosity liquids, biologically active liquids, easily foaming liquids or very small amounts of liquids. The principle is to suck in more liquid than the set range first, without blowing out the remaining liquid when transferring the liquid. First press the button to the second stop, then slowly release the button to the origin. Then press the button to the first stop to discharge the liquid with the set range, continue to hold the button at the first stop (don't press it down again), remove the tip with residual liquid, and discard it.

Correct placement of the pipette

After use, you can hang it upright on the pipette holder, but be careful not to fall off. When there is liquid in the pipette tip, do not place the pipette horizontally or upside down, so as to prevent the liquid from flowing back and corroding the piston spring.