Quality Control (QC) Samples
After a SCHEMA's Proficiency Testing round (PTs) has been completed (values for analyte concentration are assigned), surplus test samples are available for purchase.
These materials are intended to be used for internal quality control purposes and method validation. Furthermore, they could be used as training samples to assess the performance of new analysts or as corrective action samples.
A list of surplus test materials that can be purchased after the issue of the final report is available from SCHEMA.
These materials are very homogeneous and have been well characterized, both by in-house testing methods and from the results submitted by the participants in the corresponding SCHEMA Proficiency Testing scheme round (PTs).
They are provided with a certificate, indicating the assigned value for each analyte together with the acceptable range (where |z-score| <2) from the corresponding SCHEMA Proficiency Testing scheme (PTs).
Samples'stability, until the closing date of the PTs, is guaranteed by performed stability experiments; further long-term stability testing of these materials has not been carried out. However based upon expert opinion, supported by in-house data and published data on the stability of similar materials, the offered surplus SCHEMA's materials can be considered stable over the period suggested on the accompanying certificate.
Surplus samples from SCHEMA Proficiency Testing schemes (PTs) are available upon request (cost 80 €/item, transport cost not included). Please refer to the yearly programme for an indicative list of the available items , and then forward your enquiry by e-mail: firstname.lastname@example.org.