Many people who use pipettors for the first time think that the operation of pipettors is very simple, but it is not. The operation of the pipettor is the first step of a scientific experiment. It is a very basic experimental operation, but most people have prejudices against the operation of the pipettor. In fact, there is much knowledge about pipettor operation. The correct and reasonable use of the pipettor can make the experimental results more accurate and reliable. Let us take a look at how to ensure the accuracy of pipetting.
The correct use of pipettors
1. Different types of micropipettes have their own suction volume ranges. Please use the appropriate range of micro pipettors according to the volume of the solution to be taken. 2. When setting the volume, rotate from low to high, first surpass the desired set value by at least 1/3 turn, and then reverse to the set value; turn from high to low, then directly turn to the set value OK. Do not turn the volume adjustment ring beyond the use range of lowest or highest. 3. The installation of pipettor tip should adopt the rotary installation method. Place the tip of the pipettor close to the pipettor tip. While pressing down gently, the pipettor in the handle rotates 180 degrees counterclockwise. Do not use excessive force to avoid damaging the pipettor and affecting its extreme accuracy. 4. When transferring liquid, the liquid to be transferred should be sucked and released 2-3 times, so that a homogeneous liquid film can be formed on the inner wall of the tip to ensure the accuracy and accuracy of the pipetting work. 5. When aspirating liquid, the tip immersed in the liquid should be at an appropriate depth, and the liquid aspiration process should be kept as unchanged as possible. Do not immerse the micro pipettor body in the solution.
In the process of sampling and adding samples, it should be noted that the pipettor tip cannot touch other objects to avoid contamination. When aspirating general liquid, press the button with your finger to the first position, keep the micro pipettor as vertical as possible, immerse the micro pipettor in the solution, and then slowly release the button.
After waiting for 1 second, lift the tip off the liquid surface and stay on the wall for 1~3 seconds to make the drop on the outside of the tube tip slip off. Do not release the button too fast, so as to prevent the solution from rushing into the straw and corroding the piston.
When pipetting viscous or volatile liquids, it is easy to cause large volume errors. The following methods are recommended to improve pipetting accuracy. To suck a high-viscosity test solution, please cut the outlet of the micro pipettor head with a blade or scissors first, and pre-moisten it before sucking. Before pipetting the liquid, repeatedly pipettor the liquid several times to pre-wet the tip. When aspirating or discharging liquid, Z stays for a few seconds, especially when pipetting a larger volume of liquid.
Using the reversed-phase pipetting method, press the second gear when aspirating and slowly release the control button, and part of the liquid remains in the tip. After absorbing the acid or liquid, the micro pipettor should be disassembled, all parts should be rinsed clean, and then the correct combination should be restored to the original state after drying.
6. When discharging liquid, keep a certain inclination, stick the suction head to the inner wall of the container, and press the button steadily to the diyi stop point. After 1 second, press the button to the second stop point to discharge the remaining liquid. Press the button while lifting the sampler so that the tip is rubbed against the container wall to release the button. Then use the ejection function of the pipettor itself to discard the tip to the recycling device or waste device, and dispose of it properly.
1. Regular calibration and maintenance should be carried out according to the use frequency and use environment of the laboratory micro pipettor, and Z should be adjusted and maintained once every quarter. 2. Before starting work every day, check whether there is dust or dirt on the outer surface of the pipettor. If there is, wipe it off carefully. Do not use fire to grill any part of the micro pipettor, and do not absorb solutions with a temperature higher than 700C to avoid steam intrusion and corrosion of the piston. 3. After general use, clean with distilled water and neutral detergent or 60% isopropanol. Then wash it repeatedly with distilled water, remove detergent or isopropanol, and dry. A certain amount of lubricant can be used on the piston after cleaning. 4. In case of severe contamination, refer to the relevant instructions of the pipettor to disassemble the sampler and clean it. The autoclaved part of the pipettor should be autoclaved, but it should not be overheated or placed under pressure to avoid deformation and damage to the pipettor. 5. Check the accuracy of the pipettor by yourself regularly, and send it to the factory for repair if there is any problem.
Pipettors are mainly used in scientific research departments such as environmental protection, medicine, food hygiene, etc., for sampling or adding liquid in biochemical analysis and laboratory tests. It is a piston-type straw that works by using the principle of air discharge.
The capacity of the pipettor is determined by the distance that the piston moves in the piston sleeve, and the liquid is sucked out of the container and moved to a measuring instrument in another container. Correct operation and the use of pipettors can improve work efficiency and prevent fewer errors.