Claresta Lim | Product Manager

Pipetting in Wastewater Analysis

The analysis of wastewater for trace metal contaminants is crucial for the safety and health of humans and the environment. Various inorganic analytical methods can be used to measure trace elements in wastewater, including ICP-MS (inductively coupled plasma mass spectrometry) and ICP-OES (inductively coupled optical plasma spectroscopy).

*tables extracted from Perkin-Elmer Application Note, “ICP-Optical Emission Spectroscopy – Analysis of Wastewater for Metals using ICP-OES

IMPORTANCE OF PIPETTING ACCURACY

In such tests, e.g. ICP-OES, quality control standards certified by local state standardization institutes are used as starting standards for the production of working standards. A total of three standards are then used for calibration, with each metal ion represented by one standard (Tables 3 and 4). As these samples are used to calibrate the device, it is important that the liquids are pipetted using the correct technique to obtain the best accuracy and avoid sample loss due to leaks.

RECOMMENDED PIPETTES AND TIPS

To ensure optimal pipetting accuracy, micropipettes manufactured to the high accuracy and precision stated in the manufacturer's specification must be used. In addition, the disposable tips used with the pipettes should also be made of high quality material to ensure that no standard debris remains in the tip that could reduce the pipetted volume, and manufacturer approved tips are also recommended to optimize pipetting performance and prevent improper fit from causing sample leakage.

CHECKING THE PIPETTES

Pipetting accuracy is so critical here that some government guidelines or standard operating procedures (SOPs) even recommend checking the pipettes used quarterly to ensure that the data meets the manufacturer's specifications.
By using IKA pipettes and tips, it is possible to pipette with high accuracy and without sample loss.