How to Use a Micropipette
A micropipette is a precision laboratory instrument used to transfer small volumes of liquids accurately. It is commonly used in research labs, medical facilities, and other scientific settings. Here’s a step-by-step guide on how to use a micropipette:
Step 1: Familiarize Yourself with the Micropipette
Before using a micropipette, make sure you are familiar with its parts. A typical micropipette consists of the following components:
- Plunger button: Used to adjust the volume setting.
- Volume indicator: Displays the selected volume.
- Pipette tip ejector: Dispenses used pipette tips.
- Shaft: The main body of the micropipette.
- Tip ejector button: Used to eject the tip after dispensing.
- Pipette tip: The disposable attachment that comes in different sizes.
Step 2: Set the Desired Volume
Determine the volume you want to transfer by adjusting the plunger button. Micropipettes have volume adjustment settings, usually in the range of microliters (μL) to milliliters (mL). Rotate the plunger button until the desired volume appears on the volume indicator.
Step 3: Attach a Pipette Tip
Select a pipette tip that corresponds to the volume you set. Ensure that the tip fits securely onto the shaft of the micropipette. Gently push the tip onto the shaft until it is firmly attached.
Step 4: Pre-Wet the Pipette Tip (Optional)
For some applications, it is recommended to pre-wet the pipette tip. This involves pipetting and dispensing the liquid several times without a sample to eliminate air bubbles and ensure accurate volume delivery. Pre-wetting is especially crucial when working with viscous solutions.
Step 5: Aspirate the Liquid
Hold the micropipette like a pen, using a comfortable grip. Immerse the tip into the liquid you want to transfer. Depress the plunger button slowly and fully until it clicks. This will create a vacuum and draw the liquid into the pipette tip.
Step 6: Dispense the Liquid
Move the micropipette to the desired destination, such as a microcentrifuge tube or a well plate. Gently touch the tip against the side of the receiving vessel to remove any liquid clinging to the tip’s outer surface. Depress the plunger button to its first stop, and then release it to dispense the liquid.
Step 7: Eject the Used Pipette Tip
After dispensing the liquid, press the tip ejector button to release the used pipette tip into a designated waste container. Ensure proper disposal of used tips as per laboratory regulations.
Step 8: Rinse and Store the Micropipette
To maintain the accuracy and longevity of the micropipette, rinse it with distilled water or an appropriate cleaning solution. Dry the outside of the micropipette shaft and store it in a designated holder or rack.
By following these steps, you can efficiently and accurately use a micropipette for various laboratory applications. Remember to handle the micropipette with care, as it is a delicate and precise instrument.