I. Core Issue: Failure of pipetting accuracy and precision

This is the most direct and influential consequence, which is specifically manifested as

Large deviation in the volume of liquid aspirated: Unable to aspirate the preset volume of liquid, it may aspirate too much (out of the range) or too little (out of the range), resulting in distorted experimental data.

Poor repeatability: When pipetting multiple times, the actual volume of the liquid varies significantly each time, failing to meet the precision requirements of the experiment. For instance, in PCR experiments, reagents are added unevenly.

Range fit failure: Even if the pipette itself has a normal range, mismatched tips can break its designed airtight chamber structure, causing the error to be magnified when pipetting at small volumes, especially when pipetting μL level liquids.

Ii. Common Phenomena: Leakage and operational malfunctions

Mismatched pipette tips cannot form a tight seal with the pipette tip rod, which can easily cause a series of operational problems:

Leakage after pipetting: Liquid drips from the gap between the pipette tip and the tip rod, not only causing reagent waste but also potentially contaminating the operation table or other samples.

Incomplete pipetting: The residual liquid in the pipette tip cannot be completely discharged, resulting in the actual pipetting volume being less than the set value, and the residual liquid may cross-contaminate subsequent samples.

Abnormal liquid aspiration speed: Excessive or insufficient resistance during liquid aspiration, either the aspiration is slow or the liquid is drawn in too quickly, causing bubbles to form, which further affects the volume accuracy.

Iii. Potential Risks: Instrument damage and sample contamination

Long-term use of mismatched pipette tips can also cause hidden damage to the equipment and experimental samples

Damage to pipette components: When the pipette tip is too loose, repeated insertion and removal may cause wear and deformation of the pipette tip rod. When the pipette tip is too tight, forcibly removing or pulling it out may damage the sealing components inside the pipette (such as O-rings), shortening the instrument's lifespan.

Sample cross-contamination: If the pipette tip and the tip rod are not sealed tightly, the sample may seep into the gap between them. When the pipette tip is replaced later, it cannot be thoroughly cleaned, resulting in cross-contamination between different samples and affecting the reliability of the experimental results.