1. Look at the material: choose the filter tip of inert material to ensure chemical compatibility and avoid dissolution. At present, the tip of pure PP material is commonly used. There is an easy judge standard for the quality of the material used by the supplier, as long as you look at the color of the tip. Impurities in tips made of recycled plastics are very easy to be noticed by the naked eye, and after adding colors, these impurities will be “invisible”, so transparent pipette tips are usually made of better materials.
2. Judge it from the appearance: the better pipette tip quality, the better appearance. They have a smooth surface, no burrs, flat cuts, uniform shapes, and straight and non-curved surfaces, so as to ensure that the liquid is not easy to remain, and the pipetting effect is obtained.
3. Look at the certificate: if you purchase a tip without a heat source, the supplier should provide a certificate for the batch of the product.
How to use pipette tips?
1. Use the right tip In order to ensure better accuracy and precision, it is recommended that the pipetting volume is within the range of 35% of the tip.
2. Installation of the tip For most brands of pipettes, especially multi-channel pipettes, it is not easy to install the pipette tip: in order to pursue a good seal, you need to insert the pipette sleeve handle into the pipette tip and turn it left and right or shake it back and forth to tighten it forcefully.
People also use the pipette to repeatedly hit the tip to tighten, this operation will cause the tip to deform and affect the accuracy. Severely damage the pipette, so such operations should be avoided. HAWACH’s multi-channel pipette does not have an O-ring and is matched with a tip with a front stop point. It can achieve an ideal seal with only one light pressure, which is indeed a boon for users of multi-channel pipettes.
3. The immersion angle and depth of the filter tip. The tip immersion angle is controlled within 20 degrees of inclination, and it is better to keep it upright; the tip immersion depth is recommended as follows: Pipette specifications tip immersion depth 2µL and 10µL with 1 mm, 20uL and 100uL with2-3 mm, 200uL, and 1000uL with 3-6 mm, 5000 µL and 10mL with6-10 mm.
4. Tip rising It will improve accuracy for the room temperature samples. But it will reduce accuracy for the high or low temperature samples. So users should pay special attention to it.
5. Suction speed The pipetting operation should maintain a smooth and appropriate suction speed; too fast aspiration speed will easily cause the sample to enter the sleeve, causing damage to the piston and seal ring and cross-contamination of the sample.