Analyte information, gathering

Retrospective validation uses historical information gathered in actual process runs to evaluate the process. For example, batch records can provide extensive data on column performance and analytical data of fractions and final product can provide valuable information on the efficiency of the chromatographic steps in removing contaminants. Chapman67 cautions that while retrospective validation is a valid and valuable approach, it is not meant to be retroactive — validation must be done before product is released to market. 

TABLE 8.1 The elements of the information-gathering process during drug development, based on relationships between the analytical data and decision... 

In general, progress in drug development depends on data obtained from analytical instruments. Thus, how this information is derived and provided to decision makers is critical to the success of the pharmaceutical industry. LC/MS technologies have effectively and uniquely supported the productivity (quantitative processes) and efficiency (qualitative processes) needs of drug development. Future issues appear to be directed toward enhancement of the information-gathering process that focuses on the relationship between data and decision (Table 8.1). 

To conclude the investigation, the results should be evaluated in light of all information gathered about the batch and analytical testing thus far, the batch quality should be determined, and a release decision should be made. The investigation SOP should describe all activities in detail and should be followed up to this point. Once the batch has been rejected, there is no limit to further testing to determine the cause of the failure. This is critical if a corrective action and preventative measures are to be developed and implemented. 

An illustrative description of the implicit parameters was given by Harrick (1967) on the basis of a low-absorption approximation. This applies well for most organic materials, for materials of stronger absorption the Fresnel equations or the thereupon based layer algorithms mentioned in Sec. 6.4.3 should be applied. The depth from which analytical information can be gathered is conveniently characterized by the penetration depth dp. This is the distance in which the amplitude of an electric field decays to a fraction e of its initial value. For the evanescent field one finds... 

Although MS data can be used to obtain structural information, these data usually need to be extended and corroborated by other analytical techniques such as elemental analyses, molecular weight measurements, NMR, IR, and UV. The remainder of this chapter deals with information gathered from these techniques and with the integration of the data with the above-discussed MS characterization. As volatility is not a limiting factor for these determinations, the data reported include those obtained on the heavier asphaltenes. 

A biochemical evalution of human alkaline phosphatase is postponed until the above considerations have been presented. In our view, the most reasonable analytical approach is based on the measurement of L-phenyl-alanine-sensitive and -insensitive moieties along with their respective heat stabilities. To this may be added information gathered from starch-gel electrophoresis with native and heated serum and from the presence of L-phenylalanine-sensitive bands on the gels following electrophoresis. Experiments of a different type can be included, in which the serum is incubated with neuraminidase and susceptibility of the glycoprotein is established following electrophoresis. Finally, the data on L-phenyl-alanine inhibition of heat-sensitive and -insensitive moieties appear to make sense, if the population of normal subjects is divided into one with the slow-moving intestinal band and one without it. It is from this consideration and other indirect and direct inferences that the intestine is... 

Thus, the only data that can be reviewed are contained in Heinrich s books. His information-gathering methods, survey documents that may have been used, the quality of the information gathered, and the analytical systems used cannot be examined. 

In a performance-based approach to quality assurance, a laboratory is free to use its experience to determine the best way to gather and monitor quality assessment data. The quality assessment methods remain the same (duplicate samples, blanks, standards, and spike recoveries) since they provide the necessary information about precision and bias. What the laboratory can control, however, is the frequency with which quality assessment samples are analyzed, and the conditions indicating when an analytical system is no longer in a state of statistical control. Furthermore, a performance-based approach to quality assessment allows a laboratory to determine if an analytical system is in danger of drifting out of statistical control. Corrective measures are then taken before further problems develop. 

A laboratory information management system (LIMS) is a computer or computer network used to automate the acquisition and management of raw analytical data. In its simplest form, it tracks samples and test results through analytical laboratories and provides summaries of the status of these samples and tests. In its most advanced form, the system is interfaced to the laboratory s instmmentation and communication network to allow automation of data gathering, compilation, and reporting. 

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