Four steps to check the problem of small pipetting
The small amount of pipetting is the most common, and there are many reasons for this. Hawach will give a judgment order in order to help the user solve the problem.
The first step is to check the tips. Check that the tip is installed and that the tip is deformed. You can also reinstall a new tip with no abnormal appearance to confirm that it is still too small. If the condition of the small amount of liquid transfer is unchanged, go to the second step;
In the second step, check the handle. Check whether the joint between the sleeve and the tip is smooth. If there are slight scratches or rough feelings caused by friction with the tip for a long time, it is recommended to replace the sleeve. (If you need to replace the sleeve, please hand it to the supplier for disposal. The supplier also checks the piston system while changing the sleeve); check if the sleeve is blocked (when the amount of liquid suction is very small or even when it is completely incapable of aspiration, it is likely to be blocked), that is, the sleeve is removed (the sleeve is removed) Be careful when avoiding the “small wings” on the piston system. The larger diameter end of the sleeve is facing your own eyes, and the smaller diameter is facing the direction of light. If you can’t see it in the handle. When the highlight is blocked, the sliver can be used to clear the handle. After confirming that there is no abnormality in the handle, confirm whether the condition of the small amount of liquid transfer still exists. If there is no improvement, go to the third step;
In the third step, check the airtightness of the pipette. Set the pipette range to the maximum and install the tip:
(1) Pipette with a maximum range of 200 ul and above. Draw pure water and then hold it vertically for more than 15 seconds. See if there is water droplets at the tip of the tip. Even dripping, if there is no change, the air tightness is good;
(2) The pipette with the maximum range of 200ul or less, after taking the pure water, keep the tip of the tip under the water surface, stay for more than 15 seconds, and see the liquid level in the suction head. Whether there is a drop, if there is no drop, the air tightness is good. If the airtightness of the pipette is good and the amount of pipetting is too small, it is recommended that the supplier adjust the dosing screw; if the airtightness is not good, go to the fourth step;
The fourth step is to check the piston system. After removing the piston, check whether the piston is contaminated (see the “Pipelet Maintenance” written by me for the disassembly and assembly method of the piston). Clean the piston and apply the lubricating oil and then install the piston to check if the pipetting amount is too small. If you still can’t solve the problem, please hand it over to the supplier; if you find that the seal is aging or the piston is rusting and other serious problems, please also hand it to the supplier for disposal. It is generally not recommended that users replace the parts after purchasing the parts from the supplier.