Yongyue Medical tells you the tips for using pipette tips
1. Purpose: to ensure the accuracy of pipetting and the correct use of pipettes. Ensure that the pipette feeds accurately.
2. Scope of application: Adjustable pipettes are used in this laboratory.
3. Purpose of pipette:
3.1 Set volume value: a. Select the relative sampler according to the required water intake rate; the adjustable sampler should be adjusted within the allowable range yxq; the continuous adjustable sampler volume reading is composed of three-bit numbered data (The liquid volume moved by the display information), load from top (larger effective number) to bottom (least effective number) when reading, use the bottom ruler to adjust the volume to a more accurate measurement range. Adjustable rotary sampler, adjustable rotary counter-second hand yxq, azimuth angle rotary rotary rotary rotary knob, can increase the adjustable rotary rotary knob; it is more convenient to set the volume by adjusting the rotary knob. When adjusting the knob, do not use excessive force, and make sure that the value of the information displayed by the pipette does not exceed the adjustable category. The Finnpipette sampler used in this laboratory is a special instrument that can be continuously adjusted for measurement verification and pipetting. The sample addition tool has many different models and specifications. In the lower left yxq data area of F on the pendulum rod, the smallest is the larger volume value, and the volume ranges from 0.5ul to 500ul (for the volume range of various models and specifications, see the brackets below Inside). (0.5-10 people) (10-50 people) (5-50 people) (20-200 people) (50-250 people) (100-500 people)
3.2 Aspiration and discharging: first select a plastic straw suitable for placing on the specification of the sample sleeve. Clamp the tip and rotate it slightly so that there is no air gap between it and the casing specification. A pipette without a plastic pipette must not be used for the extraction of all liquids. There are two most commonly used methods for sucking and releasing liquids.
3.2.1 Forward style: a. Suction: Press a button and tighten to the first stop area; hold the sampler vertically, make the plastic pipette tip penetrate one centimeter below the liquid level, and then loosen it slowly and steadily Press the button to suck in the liquid sample, wait for another second after the pipette sucks in the liquid, then the plastic pipette tip is removed from the liquid level and stays on the wall for 2-3 seconds to make the liquid on both ends of the pipette slip off. Dispensing: Insert the tip into the cavity of the vessel and keep it tilted at 10°~40°yxq. Press the button to release the liquid stably at the first stop point, and then press the button to the second stop point after 1-2 seconds to drain the remaining liquid. Press the button, discontinuously for 1-2 seconds, lift up the sampler so that the tip sticks to the wall. Release the keys. Push the plastic straw and remove it with a chain. This pipetting method is suitable for sample addition.
4.2.2 Retreat type: a. Suction: twist the suction to the second stop; hold the sampler vertically to make the suction head penetrate the liquid sample, and then slowly and steadily release the button to inhale the liquid sample and inhale the liquid After sampling, move the tip out of the liquid level and leave it on the wall for 2-3 seconds to make the tip of the tube slip off. Dispensing: Attach the tip of the tip to the inner cavity of the vessel and keep it tilted at 10°~40°. Press the button steadily to the first stop to release the preset liquid. The liquid remaining on the tip of the nozzle is discarded with the straw or pressed to the second point and returned to the original liquid tube. This method is suitable for low-viscosity liquids, that is, liquids that are prone to foaming or very small liquids.
3.2.3 Repeated operation: Repeating the actual operation of the pipetting method can quickly and easily move the same volume of the same liquid repeatedly. Press the actual operation button down to the second stop position. Penetrate the volumetric flask tube to the deepest part of 2 to 3 mm below the liquid surface, and then gradually release the button to allow it to enter the liquid. When you need to enter the nozzle to inhale liquid, stick the nozzle on the wall of the container to avoid dripping the liquid into the bottle. Gently press the actual operation button to release the liquid at the first stop position. After the required volume of liquid is discharged, stop the button at the first stop position, and a small amount of yxq liquid that is not included in the water transfer rate range remains in the nozzle, and the liquid outside the nozzle must be included in the water transfer rate Within range. d. Repeat procedure b and c. When pipetting again, the same volume of liquid can be removed repeatedly.
3.3 Pre-wash: a. When the suction volume exceeds 10ul, in order to better ensure the accuracy and accuracy of suction, after installing a new suction tube (or changing the suction volume), the nozzle should be pre-washed , That is, first inhale the liquid sample once, and then put the sample back into the original vessel 2-3 times. The new pre-washed tip can reasonably improve the accuracy and reproducibility of the pipetting volume. The reason is that the liquid collected for the first time will produce a liquid film in the inner cavity of the straw, which leads to a deviation in the measurement verification. However, the relativity of the liquid film of the same nozzle remains unchanged in actual operation, so the cause of the deviation of the secondary liquid absorption can be ruled out. When the liquid volume of yxq is less than 10ul, only in the case of not washing, in addition, if you want to suck the sucked liquid in the liquid several times, discharge the liquid, and then put the suction nozzle out clearly and stick it to the wall, and stay Within 1-2 seconds, the accuracy and precision of liquid extraction can be ensured.
3.4 High-density, thick liquid: When sucking or discharging serum protein or thick liquid, it is best to wait a few more seconds at the first point, and then press to the second point.
3.5 Sample pipette: The choice of pipette is particularly important. The accuracy of the pipette is directly related to the quality of the pipette for sample injection. As the genetic amplification test uses a large number of suction nozzles and has a large number of practical operations, the following aspects should be paid attention to when selecting: a. The process is pure and meets the current regulations for dye-free chemicals (to prevent environmental pollution) . The appearance (well-sealed ring, thick wall, and mouth detail) makes it easier to install or unload. The wall thickness is malleable, which is not easy to cause vortex, so the accuracy is higher. There are absolutely no burrs on the mouth. The surface of the suction mouth is smooth and clean, and the wettability is very small, which prevents the liquid from staying on the surface and causing deviation. Each mouth has a shell number on the edge of the mouth, which can ensure the use of the quality tracking system software. (e) The specifications of the suction nozzle and the nozzle sleeve are kept intact to avoid accuracy or accuracy deviation caused by gas leakage. There is a liquid volume scale line, if there is insufficient water absorption, it can be dealt with in time. It can be sterilized at 121°C for 20 minutes. A straw with a pressure core should be used to prevent testing and testing, testing and testing, adding samples, or testing and testing, all of which will cause environmental pollution to actual operators.
Pipette calibration: In order to ensure the accuracy and precision of pipette pipetting, the pipette must be calibrated within the specified time (the first two years) and sent by the yxq member of the equipment department. The local metrological verification unit performs verification and saves the serial number of the verified pipette.
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