Tilavuuspipettejä

Tilavuuspipettejä, commonly known as volumetric pipettes, are precision instruments used in laboratories to accurately measure and transfer a specific volume of liquid. They are characterized by a single calibration mark on a long, narrow stem, indicating the precise volume they are designed to deliver. This design ensures high accuracy and precision, making them essential for quantitative analysis, preparing solutions, and other applications where exact liquid measurements are critical.

There are two main types of volumetric pipettes: transfer pipettes and measuring pipettes. Transfer pipettes are designed to deliver a single, fixed volume, such as 1 mL, 5 mL, 10 mL, or 25 mL. They are typically bulb-shaped with a single graduation mark. Measuring pipettes, also known as graduated pipettes, have markings along the stem to allow for the measurement of variable volumes within their capacity. However, volumetric pipettes, in the strict sense, refer to the fixed-volume transfer type due to their superior accuracy.

Using a volumetric pipette involves specific techniques to achieve the desired precision. The pipette is filled using a pipette bulb or an automatic pipette filler, drawing the liquid up to the calibration mark. Care must be taken to ensure the bottom of the meniscus aligns with the mark. The liquid is then delivered by allowing it to drain freely, with the final drop often being blown out if it is a "to contain" type pipette. Volumetric pipettes are typically made of glass and require careful cleaning and handling to maintain their accuracy. They are calibrated at a specific temperature, usually 20°C, and deviations from this temperature can affect the delivered volume.