Disposable laboratory consumables such as pipettes are widely used in tissue culture, bacteriology, clinical, scientific research and experiments.
Correct use method and steps of disposable pipette
1. Before use: When using the pipette, first check the scale, accuracy level and position of the scale line of the pipette.
2. Liquid suction: pinch the upper end of the straw with the thumb and middle finger of the right hand, insert the lower mouth of the tube into the solution to be sucked, not too shallow or too deep, generally 10-20mm, too shallow will produce suction solution and suck it into ear washing ball to smudge the solution. If it is too deep, too much solution will stick to the outside of the tube. Take the ear bulb in the left hand, connect it to the top of the tube, and slowly inhale the solution. First aspirate approximately 1/3 of the tube capacity. Pinch the mouth of the tube with your right index finger, take it out, hold it horizontally, turn the tube so that the solution contacts the solution from the lower mouth of the tube and discard.
3. Adjust the liquid level: lift the pipette up to leave the liquid level, wipe off the liquid on the outer wall of the pipette with filter paper, the end of the tube is against the inner wall of the solution container, the body of the tube is kept vertical, and the index finger is slightly relaxed, so that the solution in the tube flows from the bottom. The mouth slowly flows out until the bottom of the meniscus of the solution is tangent to the marked line, immediately with your index finger. Remove the droplet against the wall, remove the pipette, and insert it into the container that will receive the solution.
4. Release solution: If the container for the solution is a conical flask, the conical flask should be inclined at 30°, the disposable straw should be kept vertical, and the lower end of the test tube should be close to the inner wall of the bottle. Erlenmeyer flask. Release your index finger and allow the solution to slowly move along the sides of the bottle. Flow down slowly. Remove the pipette when the liquid level drops to the dispensing head and the tube touches the inner wall of the bottle for about 15 seconds. The small amount of solution remaining at the end of the tube should not flow out due to external force. Considered on time. Calculate the final remaining solution volume.