Impact of Pipetting Techniques on Precision and Accuracy (2024)

FAQs

What are the factors that affect pipette accuracy and precision? ›

Choosing the correct pipetting technique helps securing the accuracy and precision necessary for reproducible, reliable results. Especially when pipetting small volumes the influence of the pipetting technique can have tremendous effects on the experimental result.

Accuracy refers to the attribute of being correct, exact and error-free. It's the proficiency of the pipette to give a close to correct value for the liquid volume indicated in the volume setting. This defines the accuracy of micropipette. Precision refers to the reproducibility or repeatability of the calibration.

Cost and Efficiency: Accurate pipetting reduces waste of expensive resources, optimizing their use and saving time in the lab. Preventing Cross-Contamination: An accurate pipette prevents cross-contamination between samples, maintaining the accuracy of experiments, particularly in molecular biology techniques like PCR.

Step 1: The tip is immersed to the correct depth and correctly held vertically. Step 2: Inaccuracy doubles when immersing the tip too deeply. Step 3: Inaccuracy increases three to five times by immersing too deeply while holding the pipette at a 30-40° angle. Use high-quality tips intended for use with the pipette.

Pipettes provide volumetric control that surpasses manual methods such as graduated cylinders or syringes. Their design allows for precise liquid dispensing, reducing the risk of under or over-delivery, which can affect experimental results.

Inefficient pipetting can lead to issues such as transcription errors, and generally inaccurate and inconsistent results, regardless of the application.

How to calculate accuracy and precision of a pipette? ›

Finally, calculate accuracy by using the equation A = 100 x Vavg/V0, where A is the accuracy of the pipette, Vavg is the average calculated volume and V0 is the theoretical volume you tried to dispense. If the accuracy value lies in the 99-101% range, the pipette is considered normal and calibrated.

Volumetric pipettes are considered the most accurate, with the capacity to measure up to four significant figures.

Environmental Conditions: Temperature, humidity, and air pressure can impact the accuracy of pipettes. It's important to work in a controlled environment and allow pipettes to equilibrate to room temperature before use.

Reliability is one of the main reasons why accurate pipetting is so important in laboratories. For example, in a clinical laboratory if too much liquid is sucked into the pipette during a DNA sequencing task the sample may be accidently diluted.

Precision and accuracy are helpful in determining how effective a method is, and what errors might be occurring. Ideally, we would want high accuracy and precision, but that isn't always possible. Having low accuracy and/or precision can actually be helpful when evaluating certain methods.

Factors that affect measurement uncertainty, and ultimately accuracy, include the calibration standard used and the associated uncertainty of its own calibrated functions, the measurement instrument's resolution, stability, repeatability, calibration interval, and the measurement environment.

From improper operator technique to fluid viscosity issues, to variable environmental factors and internal pipette component damage, the sources of error are many and the potential for failure is real.

The accuracy of an analytical balance can be affected by various factors such as temperature, air currents, vibrations, and electromagnetic fields. Because of this, it is important to calibrate the balance regularly and use it in a controlled environment to ensure accurate measurements.