Good analytical practice

Amore, F. Good Analytical Practices, Anal. Chem. 1979, 51, 1105A-1110A. 

Barnard, Jr. A. J. Mitchell, R. M. Wolf, G. E. Good Analytical Practices in Quality Gontrol, Anal. Chem. 1978, 50, 1079A-1086A. 

Thus, to further the goals of quality and good analytical practice for which RMs are intended, EQA schemes should combine some aspects of both objectives according to the political purposes for which the scheme is being organized. Whether used for educational or licensing purposes, the ultimate intention is to ensure a certain standard of analysis is achieved and maintained in order that the user of results may be protected against errors which could be costly, in financial or human terms. 

Analysts like to make chemical measurements to the highest quality they can, and this is possible with modem instrumentation and good analytical practice. Chemical parameters are generally measured more accurately and reproducibly than parameters measured in biological systems, and the results are more reliable than values calculated by software from structure alone (e.g., calculated log P, pKa). Of all the information available to medicinal chemists, measured chemical parameters are probably the most reliable. With these thoughts in mind, it makes sense not to... 

Internal quality control is undertaken by the inclusion of particular reference materials, called control materials , into the analytical sequence and by duplicate analysis. The control materials should, wherever possible, be representative of the test materials under consideration in respect of matrix composition, the state of physical preparation and the concentration range of the analyte. As the control materials are treated in exactly the same way as the test materials, they are regarded as surrogates that can be used to characterise the performance of the analytical system, both at a specific time and over longer intervals. Internal quality control is a final check of the correct execution of all of the procedures (including calibration) that are prescribed in the analytical protocol and all of the other quality assurance measures that underlie good analytical practice. IQC is therefore necessarily retrospective. It is also required to be as far as possible independent of the analytical protocol, especially the calibration, that it is designed to test. 

Proper functioning and performance of equipment and computer systems play a major role in obtaining consistency, reliability, and accuracy of analytical data. Therefore, equipment qualification (EQ) and computer system validation (CSV) should be part of any good analytical practice. It is also requested by FDA regulations through the overall requirement that equipment must be suitable for its intended use. While in the past, equipment qualification and computer validation focused on equipment hardware and stand-alone computer systems, recently the focus has been on network infrastructure, networked systems, and on the security, authenticity, and integrity of data acquired and evaluated by computer systems. 

In contrast, the ISO Guide 25 approach (updated in 1999 to ISO Guide 17025), as expanded in ref. 14 heavily focuses on good analytical practices and adequate calibration of instruments with nationally or internationally traceable standards wherever possible. 

Proper attention to good analytical practices is important but most especially as it regards proper "blanking" of solvents, syringes, and all sample handling equipment. The high sensitivity for small amounts of material in most detector systems increases the importance of cleanliness. 

Guard columns and in-line filters alone will not ensure long life for the analytical column. They are designed to perform a specific function for a finite period of time. They, too, will be short-lived if shortcuts are taken in sample preparation and mobile phase quality control. Use of a guard column does not mean that other good analytical practices can be neglected. Shortcuts mean shorter life for any column. 

VAM sets out six principles of good analytical practice, backed up by technical support and management guidance. 

Mastery of the tools of analytical chemistry will serve you well in chemistry courses and in related scientific fields. In addition, your efforts will be rewarded with the considerable satisfaction of having completed an analysis with high standards of good analytical practice and with levels of accuracy and precision consistent with the limitations of the technique. 

The SOPs should cover all aspects of the assay from the time the sample is collected and reaches the laboratory until the results of the bioassay are reported. A description of experiments concerning the validation conducted to determine variability, limit of quantification and the quality controls should be documented for data audit and inspection the traceability is a requirement for good analytical practice. Any deviations from SOPs should be documented with justifications for deviations. 

Exploration of /rg/kg or ng/kg levels of Cr requires many precautions (Versieck and Cornells, 1989). One of the primary concerns is that for clean room conditions. Belgian atmospheric aerosols contain 37 mg /kg Cr particulate matter, with a range of 8.8 - 150 mg/kg. Good analytical practice requires a fall-out below 1 / g/m. day in the working area. The use of a laminar flow hood, if possible a class 100 one, may offer an adequate solution at a modest price. 

In conclusion, analytical chemistry is an underlying factor in essentially all aspects of toxicological work. It is evident from these examples that the sophistication of the analytical methods available for use can to a large extent determine the complexity of the toxicological problem that can be approached and solved. The best analytical approach is designed to meet the specific needs and emphasis of the toxicological research and is consistent with good analytical practices. 

Amore, F., Good Analytical Practices as an Alternative to Standard Methods, Licensing and Certification. In Quality Assurance of Environmental Measurements, Information Transfer,... 

If, as good analytical practice demands, the standardization titration also contains the same amoimt of indicator solution as each of the determination runs, then the indicator errors will be almost negligible. 

Good analytical practice is the basis of all the GxP (x = L, M, etc.) or cGxP standards long since mandatory in the pharmaceutical industry, and now finds an equally willing host in accreditation to ISO/lEC 17025. This new role is being driven in no small part by the conversion of ISO guide 25 in recent years to ISO/lEC standard 17025. 

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