Analytical instrumentation, impact

The computerized systems, both hardware and software, that form part of the GLP study should comply with the requirements of the principles of GLP. This relates to the development, validation, operation and maintenance of the system. Validation means that tests have been carried out to demonstrate that the system is fit for its intended purpose. Like any other validation, this will be the use of objective evidence to confirm that the pre-set requirements for the system have been met. There will be a number of different types of computer system, ranging from personal computers and programmable analytical instruments to a laboratory information management system (LIMS). The extent of validation depends on the impact the system has on product quality, safety and record integrity. A risk-based approach can be used to assess the extent of validation required, focusing effort on critical areas. A computerized analytical system in a QC laboratory requires full validation (equipment qualification) with clear boundaries set on its range of operation because this has a high... 

It is widely understood within the industry that risk is defined as the combination of the probability of harm and the severity of that harm. Within the pharmaceutical industry whenever risk is considered the equipment or product being assessed must be viewed in the context of the protection of the patient. From our perspective, analytical instruments may impact on the validity of data that determines the safety and efficacy of drug products, or on the quality of the drug product. They may also impact on the identity or potency of the drug product and therefore it is important to ensure that risk management is performed throughout the complete life cycle of the instrument. 

Two major developments in the past decade increased the impact of Chemometrics the development of computers and micro-electronics and the advancement of analytical instrumentation. 

In today s process analytical instruments, where response noise and reproducibility have been greatly improved, it is quite possible to encounter outliers that are not easily visible by plotting the raw data. These outliers could involve single variables or samples that have relatively small deviations from the rest of the data, or they could involve sets of variables or sets of samples that have a unique multivariate pattern. In either case, these outliers, if they represent unwanted or erroneous phenomena, can have a negative impact on the calibration model. 

At the bottom end of the scale, many cheap 8-bit microcomputers are finding their way into analytical applications. These include machines such as the Apple and the Commodore PET (which incorporates the IEEE-488 bus) as well as many others. Although computers such as these lack the computing power and sophisticated interfacing abilities of the MINC, there are many applications for which they are quite powerful enough, whilst their low prices enable them to be used in a wide range of situations where computers have not previously been employed for reasons of cost. The impact which microcomputers and microprocessors have had upon analytical instrumentation is reviewed in Ref.7). 

In a recent survey on instrument use in drug discovery and development [7], improved software, computing power, and automation were the three technologies cited as having the most impact on the future of analytical instrumentation. The results of this survey, summarized in Fig. 1, also show that other instrumentation... 

In the past, analytical measurements during a process were always performed off-line or, at best, at-line. In recent years, the trend is towards on-line analysis. This has a significant impact on the way scientists use analytical instruments and how they can adapt existing equipment to work in the often harsh environments of processes in the pharmaceutical, food and other industries. 

Computers, software and computation are topics worthy of deliberation as they impact data quality but are only very briefly touched upon. Computers serve analytical chemistry in three basic ways by instrument operation, computation of analytical data, and laboratory management/preparation of technical and scientific reports. Analytical instrumentation is invariably computer-controlled, and this is not only peripheral (nice) and extremely helpful in increasing analytical output and decreasing staff requirements, but is absolutely essentia] when running complex equipment. Furthermore, complex... 

INAA, gamma counting, XRF, etc.) cannot be performed manually. One is led to question whether reliance on computer control, treatment of complex analytical instrumentation as black boxes and their operation by less well-trained and less qualified operators has a negative impact on the quality of output. One should also consider the performance of the vast proliferation of off-the-shelf commercial statistical and spreadsheet software, as well as custom-made software and conduct verification with model sets of data. One has to be aware that algorithms used as basis for commercial software associated with analytical instruments may be philosophically different from those utili-lized by the analytical scientist. Software, custom-designed for the author for FAAS calculations was rigorously tested with model input data and manual calculations. 

The concept of Life Cycle Assessment (LCA) is described in Chapter 4. As an analytical instrument for generating information on resource consumption and environmental impact, LCA is increasingly finding acceptance for the evaluation of materials, processes and products in a wide range of situations. 

Figure 9.5 Schematic diagram of a direct insertion probe for solids and high boiling liquids. The sample is placed into the cavity in the tip of the probe. When not in use, the cutoff valve is closed, and gas samples can be introduced by opening the stopcock shown. The black dot at the center of the square shows the point at which the electron beam impacts the sample. (From Ewing, G.W., Mass spectrometry, in Ewing, G.W. (ed.). Analytical Instrumentation Handbook, 2nd edn., Marcel Dekker, Inc., New York, 1997. Used with permission.)...

The field of analytical instrumentation systems is one of the most rapidly progressing areas of science and technology. This rapid development is facilitated by (1) the advances in numerous areas of research that collectively provide the impact on the design features and performance capabilities of new analytical instrumentation systems and by (2) the technological and market demands to solve practical measurement problems. 

The characteristics of analytical hardware changes over time due to contamination, and normal usage of parts. Examples are the contamination of a flow cell of a UV detector, the abbreviation of the piston seal of a pump or the loss of light intensity of a UV detector. These changes will have a direct impact on the performance of analytical hardware. Therefore the performance of analytical instruments should be verified during the entire lifetime of the instrument. 

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