Micropipettes are used for accurately transferring small volumes of liquid in the milliliter and microliter range. We will cover three basic sizes of these handy little instruments.
The liquid is drawn into, and dispensed from a disposable pipette tip - The disposable tip is changed between liquid transfers. Pre-rinse every new pipette tip with the liquid to be pipetted.
Despite the differences in micropipette shapes and sizes, they have the same basic parts:
The volume is set by turning the dial. When decreasing the volume, slowly turn the dial to reach the required volume. Be careful not to overshoot. When increasing the volume, pass the desired volume by one-third turn and then slowly decrease the volume to the final mark.
The display is read from top to bottom. For a P-1000, the volume is given in milliliters. The top position is the ones place, the middle is the tenths place, and the bottom is the hundredths place. In the P-200, the top position is the hundreds place, the middle is the tens place, and the bottom is the ones place. The top position in the P20 is the tens place, the middle is the ones place, and bottom is the tenths place.
Normal operations consist of the following steps:
Preparation: Hold the instrument in a nearly vertical position. Depress the plunger smoothly to the first stop.
To ensure maximum accuracy, please consider the following: operator consistency, pipettes are calibrated “to deliver” and not to “contain”, and pipettes should be calibrated at periodic intervals.
View other Cell Culture videos.