The use and precautions of Changfeng graduated quantitative pipette

1. Types and specifications of Changfeng graduated quantitative pipettes

Changfeng graduated quantitative pipettes are divided into two types: complete outflow type and incomplete outflow type according to different uses and designs. They differ in the way they are used, but both are capable of providing precise liquid measurements.

Complete Outflow Graduated Pipettes: This type of pipette is designed to blow out any residual liquid at the tip of the pipette as it draws up the liquid, ensuring that the liquid in the pipette flows out completely and that the total volume of solution injected into the pipette is used as the basis for measurement. This type of pipette is used in experiments where precise liquid volume is required, and is suitable for a variety of liquid transfers that require a high degree of accuracy.

Incomplete Outflow Graduated Pipettes: Unlike complete outflow pipettes, incomplete outflow pipettes do not require that residual liquid be blown out of the tip of the pipette during use. The design takes into account the natural flow of liquids, so liquids that do not flow completely out of the tip are not counted, and there is no need to blow out the residual liquid when using the pipette. It is suitable for experiments requiring slightly lower precision.

Changfeng graduated pipettes are available in a wide range of specifications, including 0.1, 0.2, 0.5, 1, 2, 5, 10mL, etc., which can meet the needs of liquid measurement in different experiments. Choosing the right specification is crucial to the accuracy of the experiment.

2.The use of Changfeng graduated quantitative pipette

The use of Changfeng graduated pipettes is simple but requires attention to detail to ensure accurate liquid measurement. The correct way to use them is as follows:

Preparation: Before use, first confirm the cleanliness of the graduated pipette to ensure that there are no residual impurities in the pipette. Then, insert the tip of the pipette tube approximately 1cm below the surface of the liquid, ensuring that the graduated surface is always facing the operator.

Aspirate the liquid: Use an earwash ball or suction ball to draw the liquid into the pipette, taking care to draw the amount of liquid to a position slightly above the target scale. At this point, gently block the mouth of the tube with your index finger to ensure that the liquid does not overflow.

To adjust the amount of liquid: move the pipette above the liquid level, keep it vertical and slowly release the index finger. The excess liquid will flow back into the reagent bottle until the lowest point of the crescent surface of the liquid in the pipette is tangent to the desired scale.

Removing the pipette: Once the amount of liquid in the pipette has been adjusted to the exact scale, press the index finger against the mouthpiece again and lightly touch the tip of the pipette to the wall of the container, pausing for a moment to ensure that the liquid on the inside of the pipette flows completely into the container. At this point, you can move the straw to the target container, release the index finger, so that the liquid inside the straw naturally flow out.

3.Changfeng scale quantitative pipette selection and precautions

In the experimental process, it is very critical to choose the appropriate specifications of the graduated pipette. If the choice is not appropriate, it will lead to inaccurate liquid measurement, thus affecting the reliability of the experimental results.

Selection of specifications: Pipettes of different specifications are suitable for transferring liquids of different volumes. Usually, 0.1mL, 0.2mL and other smaller sizes of pipettes are used for micro-experiments, while 1mL, 5mL, 10mL and other larger sizes of pipettes are suitable for larger volumes of liquid measurement. When choosing pipettes, avoid using pipettes that are too large or too small. For example, if you need to take 0.1mL of liquid, the use of 10mL pipette may lead to too large an error, affecting the accuracy of the experiment.

Avoiding Errors: The accuracy of pipettes may vary in different sections of the pipette, especially in the lower section of the scale, so avoid picking up liquids close to the lower section when using the pipette. If you need to measure 0.6 mL of liquid, you can use a 1.0 mL pipette and draw up to 1.0 mL and then put back the excess liquid, accurate to 0.6 mL.

Accuracy issues: when using graduated pipettes, you should ensure that the liquid in the pipette crescent surface is exactly tangent to the desired scale line, to avoid liquid residue or excess, to ensure the accuracy of the measurement.

4.Conclusion

With its precise scale design, Changfeng graduated quantitative pipette is widely used in all kinds of chemical, biological and environmental testing and other experiments. In the process of using them, reasonable selection of pipette specifications, ensuring the standard operation and avoiding errors are the keys to ensure the accuracy of experimental results. By mastering the correct use methods and techniques, the graduated pipettes can be fully utilised in experiments to enhance the efficiency and precision of experiments.