Sample preparation, generally quality assurance

The design of an assay is, in large measure, prospective quality assurance. The factors that are likely to affect the results of the assay must be defined and controlled to the greatest extent possible. Once the general outlines of an assay have been established, key features should be examined, including optimization of sample preparation, sample stability, choice of standards, assay range, assay repeatability, optimization of separation, and optimization of detection. 

CRMs can be either analytical standards (Section 2.2.1), or calibration solutions that are solutions of an analytical standard at a certified concentration in a clean solvent, or natural material (matrix) CRMs that are prepared from material found in nature, i.e., are surrogates for the real samples to be analyzed. Matrix CRMs are invaluable as tools in quality assurance and quality control (QA/QC) in analytical laboratories, as discussed in Chapter 10. However, CRMs are generally too expensive to be used as everyday QCs and are generally used as method development tools or in occasional checks of the laboratory QCs (Section 2.5.3). 

Annex 3 (Manufacture of Radiopharmaceuticals) is the only part of the GMP framework entirely dedicated to radiopharmaceuticals [10]. Preparation of radiopharmaceuticals using authorised generators and kits is excluded from this Annex. The production of radionuclides in reactors and cyclotrons is a physical process and is regarded as a non-GMP activity. Annex 3 describes general GMP principles (quality assurance, personnel, premises and equipment, documentation, production, quality control, reference and retention samples, distribution) in relation to radiopharmaceuticals. As with other medicinal products, other GMP annexes may be applicable, for instance Annex 1 Manufacture of Sterile Medicinal Products [11]. 

The broad spectrum of analytical techniques available today is covered in this handbook. It starts with general articles on purpose and procedures of analytical chemistry, quality assurance, chemometrics, sampling and sample preparation followed by articles on individual techniques, including not only chromatographic and spectrometric techniques but also e. g. immunoassays, activation analysis, chemical and biochemical sensors, and techniques for DNA-analysis. 

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