Laboratory quality systems analytical methods

Before the designation, the laboratories developed their laboratory methods for testing, constructed and made operational their laboratory quality system and obtained its accreditation, and continued the participation and successful performance in the OPCW proficiency tests (PT). Analytical methods in particular and a certain level of quality assurance systems have existed in the laboratories, involved often in research, well before their designation. Participation in the international interlaboratory... 

Because an LSMBS is almost certain to involve more than one laboratory in the analytical phase, results obtained by multiple laboratories must be internally and externally consistent. For this reason, the use of a single method in all analyses, if possible, is advantageous. The method must conform to quality criteria and must be rugged, i.e., must be satisfactory for all analytes in all commodities, with instruments and data acquisition systems from various manufacturers. 

The guidelines stress, however, that internal quality control is not foolproof even when properly executed. Obviously it is subject to errors of both kinds , i.e. runs that are in control will occasionally be rejected and runs that are out of control occasionally accepted. Of more importance, IQC cannot usually identify sporadic gross errors or short-term disturbances in the analytical system that affect the results for individual test materials. Moreover, inferences based on IQC results are applicable only to test materials that fall within the scope of the analytical method validation. Despite these limitations, which professional experience and diligence can alleviate to a degree, internal quality control is the principal recourse available for ensuring that only data of appropriate quality are released from a laboratory. When properly executed it is very successful. 

Intuitively we can feel that the economical value of the analytical result is related to its quality. The quality of an analytical result depends upon two factors first of all we should know how confident we are about the produced result. In fact, an analytical result without an explicit or implicit (by the number of significant figures) indication of its precision has no quality at all. Second, the quality of the analytical result depends on how well the sample represents the system of its origin. The sample may be contaminated or may be modified because of inappropriate storage and aging. In other instances, when the sample is taken from a chemical reactor in which a chemical reaction is occurring, the constitution of the reactor content is usually time varying. Because of inevitable time delays in the analytical laboratory, the constitution of the sample will not anymore represent the actual constitution in the reactor at the moment when the analytical result is available. Therefore, both the precision of the analytical method and the analysis time are important indicators for the quality of an analytical result . ... 

An important consideration in the development of quality systems in development is to ask the question What business does development support Development does not mean exclusively working to develop formulation or analytical methods many activities are directly involved in support of clinical material production. Laboratory leadership has the responsibility to consider carefully the customers and functions of an analytical development department. As part of this consideration, several key questions are useful in defining the business and quality standards ... 

Every analytical laboratory, governmental, private, or university, has a standard set of procedures that provide both general and specific information to laboratory members. These fall into certain categories, including the laboratory s standard operating procedures (SOPs), quality assurance/quality control manuals (QA/QC manuals), procedural manuals, analytical method files, and laboratory information management systems... 

When the analytical laboratory is not responsible for sampling, the quality management system often does not even take these weak links in the analytical process into account. Furthermore, if sample preparation (extraction, cleanup, etc.) has not been carried out carefully, even the most advanced, quality-controlled analytical instruments and sophisticated computer techniques cannot prevent the results of the analysis from being called into question. Finally, unless the interpretation and evaluation of results are underpinned by solid statistical data, the significance of these results is unclear, which in turn greatly undermines their merit. We therefore believe that quality control and quality assurance should involve all the steps of chemical analysis as an integral process, of which the validation of the analytical methods is merely one step, albeit an important one. In laboratory practice, quality criteria should address the rationality of the sampling plan, validation of methods, instruments and laboratory procedures, the reliability of identifications, the accuracy and precision of measured concentrations, and the comparability of laboratory results with relevant information produced earlier or elsewhere. 

Quite obviously, the quality of analytical results strongly depends on the representativeness of the sample examined, the appropriateness of the pretreatment procedures applied for the quantitative conversion of analytes into detectable forms, and the btness for purpose of the laboratory setting. Because of the low concentration and the numerous interferences which affect the various detection systems, measurements methods must be thoroughly validated. Even if values obtained by several laboratories for PGEs concentrations in environmental and biological samples were compliant with the basic requirements of quality assurance (QA) and internal quality control (QC), striking differences have been... 

Qualification activities are normally associated with buildings, facilities, utility systems (e.g., water, air handling, Clean-in-place/Steam-in-place (CIP/SIP), and compressed gases) major equipment (including laboratory instrumentation), whereas validation likely is in reference to those confirmatory tasks related to processes and analytical methods. In simplistic terms, validation (and qualification) can be defined as documented evidence that a process, activity, or piece of equipment can consistently meet its predetermined acceptance criteria and quality attributes. This section will be dedicated towards outlining the requirements for validation of manufacturing processes, as... 

Reproducibility, as defined by ICH, represents the precision obtained between laboratories with the objective of verifying if the method will provide the same results in different laboratories. The reproducibility of an analytical method is determined by analyzing aliquots from homogeneous lots in different laboratories with different analysts, and by using operational and environmental conditions that may differ from, but are still within the specified, parameters of the method (interlaboratory tests). Various parameters affect reproducibility. These include differences in room environment (temperature and humidity), operators with different experience, equipment with different characteristics (e.g., delay volume of an HPLC system), variations in material and instrument conditions (e.g., in HPLC), mobile phases composition, pH, flow rate of mobile phase, columns from different suppliers or different batches, solvents, reagents, and other material with different quality. 

When preparing a method comparison study, the analytical methods to be studied should be established in the laboratory according to written protocols and stable in routine performance. Reagents are commonly supplied as ready-made analytical kits, perhaps implemented on a dedicated analytical instrument open or closed system). The technologists performing the study should be trained in the procedures and associated instrumentation. Further, it is important that an internal quality control system is in place to ensure that the methods being compared are running in the in-control state. 

From R D to quality control, rheology measurements for each phase of the product development life cycle involve raw materials, premixes, solutions, dispersions, emulsions, and full formulations. Well-equipped laboratories with stress- and strain-controlled oscillatory/steady shear rheometers and viscometers can generally satisfy most characterization needs. When necessary, customized systems are designed to simulate specific user or process conditions. Rheology measurements are also coupled with optic, thermal, dielectric, and other analytical methods to further probe the internal microstucture of surfactant systems. New commercial and research developments are briefly discussed in the following sections. 

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