Precautions for pipette tips

First, special tips.

Special tips are specially designed tips for special samples or special applications. There are mainly the following categories: the first category is gel tips (also called spot tips): the tip of the tip is either flat or very thin, mainly used for electrophoresis experiments; the second category is wide mouth tips: the tip tip caliber is larger than the general tip, mainly used for removing large molecule solutions such as proteins; the third category is low adsorption tips: the inner wall of these tips is specially treated to reduce the surface adsorption, which can be used to remove viscous liquids; the fourth category is the extended tip: mainly used to take liquid in containers such as volumetric flasks; the fifth category is the external piston tip: mainly used on special pipettes such as external piston pipettes and continuous dispensers.

Second, the adaptability of pipette tips.

This point about the adaptability of pipette tips is a growing concern for users nowadays, why? Because not all pipette tips can be used on any brand of pipette with the corresponding range, so once again, we remind our users to pay attention to the adaptability of the tips when purchasing them. There are several ways to understand the suitability of the tips: First, the specificity of the tips. Some brands can only use their own standard pipette tips for certain pipette series, but not for others. For example, Rainin's multichannel pipettes must use their own LTS tips; second, the degree of tip adaptation. The most common scenario is that a pipette can be used with multiple tips, but the pipetting effect varies with the different tips installed. In general, the standard pipette tips are the best, but some brands have good tips, such as Axygen. Third, the pipette tip and the pipette range should be adapted. In general, the volume of the tip should be greater than or equal to the maximum range of the pipette, such as 200ul tips can be used for the maximum range of 20ul, 100ul and 200ul pipettes; fourth, a large range of pipettes (5ml, 10ml and 20ml) tip specificity. All major pipette brands often need to use their standard pipette tips for large-range pipettes, and it is more difficult to find a replacement. Therefore, if we need to purchase a pipette tip, it is recommended that we tell the supplier the type of tip we are using or at least provide the brand and range of pipette we are using.

Third, biological contamination.

Nowadays, more and more users are asking for pipette tips that are free of RNA enzymes, DNA enzymes, DNA, thermogenic and ATP contamination. This is a good phenomenon, but Lebel has to remind two more points: First, autoclaved tips are not completely guaranteed to be free of biological contamination, and steps such as gamma ray processing are required to ensure that they are free of biological contamination. Therefore, it is almost impossible for the user to process the common tips into bio-contamination-free tips, and the purchased bio-contamination-free boxed tips should be provided with the corresponding certificate indicating the testing data of the corresponding items. There is no data on the certificate or even no certificate for the suction tip, it is not possible to prove that it is completely contamination-free; secondly, the bagged suction tip is even more impossible to guarantee the absence of biological contamination. As long as the suction tip is in contact with the air, there is a possibility of biological contamination, and the ordinary self-sealing bag can not guarantee that the suction tip is completely free of air during storage and transportation; in addition, the self-sealing bag is punctured by the suction tip, which also happens from time to time. Therefore, if you have high requirements for the suction head, and then purchase must be clear from the supplier whether the suction head with the corresponding project test data marked on the certificate.

Fourth, with cartridge suction head.

With cartridge suction head is in the upper end of the suction head has a cartridge (generally white). This cartridge is generally made of polypropylene, similar to the cigarette filter structure. Thanks to this cartridge, the sample cannot enter the pipette, thus protecting the pipette components from contamination and corrosion and, more importantly, ensuring that there is no cross-contamination between samples. Therefore, cartridge tips are also an important tool for pipetting volatile and corrosive samples. Of course, the price of cartridge tips is relatively high compared to general tips and the market share in China is very low. Moreover, there are few domestic cartridge tips available, and their filtration effect is not satisfactory.