How to use the pipette
Method 1: Advance pipetting method (applicable to conventional liquid pipetting)
1. Adjust the scale or reading of the sampling gun to the required amount of liquid to be aspirated, and install a suitable pipette tip.
2. Press the button to the first stop position (with obvious blocking feeling) and keep it to squeeze out the air in the suction head to form a negative pressure in the suction head.
3. Immerse the tip into the depth of 2 to 3 mm below the surface of the liquid to be removed, then slowly release the button, and the liquid enters the tip under the effect of atmospheric pressure. After inhaling the required amount of liquid, withdraw the sample gun from the liquid surface and wipe off the liquid on the outside of the tip, taking care not to touch the tip of the tip.
4. Move the sampling gun to the container to be filled with liquid, so that the pipette tip is located near the liquid level of the container. Gently press the button to the stop position to let the liquid slowly flow out. When the liquid will run out, continue to press the button to the second stop point, and let the tip of the tip gently touch the container wall above the liquid surface to avoid air bubbles.
5. Continue to hold down the button, withdraw the sampling gun, and discard the tip in a specific vessel holding the contaminated tip, and release the button to the starting position. If you need to continue to aspirate, replace the tip and repeat the above operation. Otherwise, hang the sample gun vertically on the sample gun frame.
Method 2: Reverse pipetting method (suitable for the transfer of high-viscosity liquids and / or liquids that are prone to foaming, and the transfer of very small amounts of liquids.)
1. Adjust the required scale, after installing the suction head, press the button down to the second stop point.
2. Immerse the tip into the depth of 2 to 3 mm below the liquid surface, and then slowly release the button to suck in the liquid. After aspiration is complete, withdraw the tip from the liquid surface and apply it diagonally to the wall of the reagent bottle to drain excess liquid.
3. Gently press the button to the first stop point to release the liquid.
4. After the liquid is dispensed, a small amount of liquid that is not included in the pipetting volume remains in the tip. The residual liquid can be thrown away with the tip or returned to the original container.
Note: 1. If the pipetting volume is too large, there will be no extra space in the pipette tip to accommodate excess residual liquid when the pipetting method is reversed, so this method is often not suitable for the removal of large amounts of liquid.
2. When you need to remove more than 4 ml of viscous or foamy liquid, you can use the forward method to suck the liquid, and then slowly press the button to the first stop point to slowly release the liquid. At this time, the liquid outside the tip should be included in the pipetting volume.
Method 3: Repeated pipetting method (suitable for rapid and easy transfer of the same amount of the same liquid.)
1. Adjust the required scale, after installing the suction head, press the button down to the second stop point.
2. Immerse the tip into the depth of 2 ~ 3 mm below the liquid surface, and then slowly release the button to suck in the liquid. After aspiration is complete, withdraw the tip from the liquid surface and apply it diagonally to the wall of the reagent bottle to drain excess liquid.
3. Gently press the button to the first stop point to release the liquid. After the liquid dispensing is completed, let the button stop at the first stop point, and a small amount of liquid not included in the pipetting volume remains in the tip. At this time, the droplet outside the tip should be included in the pipetting volume.
4. The tip is immersed 2 to 3 mm deep under the liquid surface, and then slowly release the button to re-absorb the liquid.
5. Repeat steps 3 and 4 to remove the same volume of the same liquid multiple times.
Method 4: Whole blood removal method (such as deproteinization step used in blood glucose measurement)
1. Step 1 and step 2 of the forward method are used to make the tip full of blood. Use a clean, dry tissue paper to carefully wipe off the blood outside the tip.
2. Immerse the suction head under the liquid surface, and then press the button to the first stop position. During operation, make sure that the suction head is always under the liquid surface.
3. Slowly release the button to return the button to the starting position, at this time the reagent is gradually drawn into the tip. Then press the button to the first stop position, and then slowly release the button. Repeat this operation until all the liquid to be transferred (such as whole blood) is transferred to the solution. Care should be taken so that the tip is always below the liquid level.
Finally, press the button again to the second stop point, and the liquid in the suction head can be completely discharged.
Precautions for use:
1. Before adding the sample, be sure to check whether the pipette tip is tightened to avoid liquid leakage or inaccurate liquid extraction.
2. Make sure that the tip of the pipette tip is always under the liquid surface during the whole liquid suction process, that is, to prevent the suction sample from being inaccurate.
3. Be sure to wipe off the liquid around the suction head before draining the liquid after the liquid suction is completed, especially pay attention to this point when the liquid volume is small. But to prevent touching the tip of the tip.
4. The action of sucking liquid and discharging liquid must be slow, because when the action is too fast, the liquid is adsorbed on the wall of the suction head due to the surface tension, resulting in inaccurate pipetting. The higher the viscosity of the liquid taken, the more attention should be paid to this problem.
5. When draining the liquid, gently tip the tip of the tip to contact the container wall when the liquid is drained, so as to avoid the formation of bubbles in the sampled container and affect the subsequent reaction.
6. After the sample is added, the used tip should be discarded before releasing the button to the starting position to prevent the residual liquid in the tip from being sucked back to the tip, causing cross contamination. Especially when conducting experiments related to molecular biology, such as PCR sample loading operation, due to the extremely strong amplification ability of PCR, if the improper operation causes the aerosol of DNA-containing liquid specimens to adsorb on the gun head, it is very It is easy to cause false positives in the experiment.
7. Pay attention to the use of disposable tips to avoid cross-contamination.
Ningbo Siny Medical Technology Co., Ltd
