QA/QC system is described, measurement uncertainty, traceability of analytical results, reference materials, interlaboratory comparisons and the problems and challenges during method validation process are presented.
One of the main developmental trends in chemical analytics is the determination of analytes at ever decreasing detection levels in samples with increasingly complex matrices. This is an extremely difficult and complicated task therefore it poses a great challenge to analytical chemists, and it requires that appropriate attention be paid to the Quality Assurance and Quality Control (QA/QC) of the obtained measurements. In this article QA/QC system is described. Following topics are discussed: (1) measurement uncertainty, (2) traceability of analytical results, (3) reference materials, (4) interlaboratory comparisons and (5) method validation. The problems and challenges during method validation process are presented.