Quality assurance and process control

pH strips or indicator paper, Merckoquant^® test strips and colorimetric and titrimetric test kits (Aquamerck^®, Microquant^®, Aquaquant^®)

The process is inspected using appropriate standards. The concentration of these standard solutions should correspond to the graduation which is close to the expected concentration of the sample.

The most suitable standard solutions are described in the package insert for the relevant test kits. If the test yields the predetermined concentration of the standard solution, then this means that the entire analysis system is operating correctly.

Check of RQflex and RQflex plus

For this, we offer RQcheck Check Set 1.16957.0001

Check of the entire analysis system

(Test strips, instrument, pipettes and handling)

For this check, the standard solutions are measured multiple times. The most suitable standard solutions are described in the package inserts of the relevant test kits.

Please note that the concentration of the standard solution should approximate the concentration of your sample.

If the test yields the predetermined concentration of the standard solution within a tolerance of ± 10%, then this means that the entire analysis system is operating correctly.

Checking interferences by matrix effect

Foreign substances can interfere with the determination. To determine these interferences, there are two methods:

• Identification of matrix effects by means of dilution
  This method is especially suitable for samples with analyte content that falls within the upper half of the measuring range of the corresponding test kit.
• Identification of matrix effects by means of standard addition
  This method is especially suitable for samples with analyte content that falls within the lower half of the measuring range of the corresponding test kit.

Spectroquant^® NOVA und Pharo photometer have an instrument-supported Analytical Quality Assurance (AQA) and support your internal quality control.

In connection with Internal Quality Control measures (IQC), pipettes should be tested at regular intervals. This is usually done by weighing the volume of a liquid on a calibrated precision balance.

Such a balance is, however, not always readily available. With Spectroquant^® PipeCheck 1.14962.0001 you can check your pipettes and document the measurement results accordingly, even if you don’t have a balance.