Method Development Software Tools

Three method development cases studies of pharmaceuticals are used to illustrate the logical sequence in fine-tuning conditions to meet method goals. These are  

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For presenting the results of the 3D-CT measurements the software tool 3D-CTViewer [12] was designed and developed under the visualization developer language IDL [13]. In this package both typical methods for 3D-visualization, the surface and the volume rendering technique [14], are implemented. 

Assessing the resources available for method development should also be done before beginning a project. The resources available include not only HPLCs, detectors, and columns, but also tools for sample preparation, data capture and analysis software, trained analysts, and especially samples representative of the ultimate analyte matrix. Also, it should be considered whether a fast, secondary method of analysis can be used to optimize sample preparation steps. Often, a simple colorimetric or fluorimetric assay, without separation, can be used for this purpose. A preliminary estimate of the required assay throughput will help to guide selection of methods. 

The brain s remarkable ability to learn through a process of pattern recognition suggests that, if we wish to develop a software tool to detect patterns in scientific or, indeed, any other kind of data, the structure of the brain could be a productive starting point. This view led to the development of artificial neural networks (ANNs). The several methods that are gathered under the ANN umbrella constitute some of the most widely used applications of Artificial Intelligence in science. Typical areas in which ANNs are of value include ... 

One issue related to supporting a metabolic stability assay with HPLC/MS/MS is the need to set up an MS/MS method for each compound. While it may only take 10 min to infuse a compound solution and find the corresponding precursor and product ions (along with minimal optimization of the collision energy), the processes of MS/MS development would require 4 hr per day if one wanted to assay 25 compounds per day. MS vendors have responded to this need by providing software tools that can perform the MS/MS method development step in an automated fashion. Chovan et al.68 described the use of the Automaton software package supplied by PE Sciex (Toronto, Canada) as a tool for the automated MS/MS method development for a series of compounds. The Automaton software was able to select the correct precursor and product ions for the various compounds and optimize the collision energy used for the MS/MS assays of each compound. They found that the Automaton software provided similar sensitivity to methods that would have been developed by manual MS/MS procedures. Chovan et al. also reported that the MS/MS method development for 25 compounds could be performed in about an hour with the Automaton software and required minimal human intervention. 

Tandem MS has been more or less successfully performed with a wide variety of analyzer combinations. What analyzers to combine for a certain application is determined by many different factors, such as sensitivity, selectivity, and speed, but also size, cost, and availability. The two major categories of tandem MS methods are tandem-in-space and tandem-in-time, but there are also hybrids where tandem-in-time analyzers are coupled in space or with tandem-in-space analyzers. Moreover, the ongoing development of faster electronics and high-voltage circuits as well as better software tools and hardware control devices constandy open up new possibilities of making innovative combinations of analyzers for specific applications. In this chapter a few examples of commercially available tandem MS instruments are presented. A brief summary of their weaknesses, strengths, and main areas of applications is given. 

An important aspect of our AI application is the attention paid to including well-established Fortran programs and database search methods into the decision structure of an expert system network. Only certain AI software tools (such as TIMM) effectively handle this critical aspect for the analytical instrumentation field at this time (57-60)> The ability to combine symbolic and numeric processing appears to be a major factor in development of multilevel expert systems for practical instrumentation use. Therefore, the expert systems in the EXMAT linked network access factor values and the decisions from EXMATH, an expert system with chemometric/Fortran routines which are appropriate to the nature of the instrumental data and the information needed by the analyst. Pattern recognition and correlation methods are basic capabilities in this field. 

Given the nascent nature of these software tools, SGX developed its own method to evaluate or score the diffraction quality. The SGX system is based on two established software programs, d TREK (Pflugrath, 1999) and Mosflm (Leslie, 1992). These programs index diffraction images to determine the appropriate Laue group. In addition, they provide an analysis of the properties of the... 

Our failure risk analysis and opportunity method and iterative software tool, as part of our New Product Process Innovation (NPPI) Tool Library, promotes systematic collaboration and team-oriented engineering thinking when a new pharmaceutical manufacturing system process and/or product are developed. (We call it opportunity method too, since most risks, if not all, offer new opportunities for innovation.) It is based on our generic process failure risk analysis method that could be apphed to literally any process that involves risk—and innovation is a very risky process. 

Unfortunately, it is this writer s opinion that, considering the voluminous publications on chemometrics applications, the number of actual effective process analytical chemometrics applications in the field is much less than expected. Part of this is due to the overselling of chemometrics during its boom period, when personal computers (PCs) made these tools available to anyone who could purchase the software, even those who did not understand the methods. This resulted in misuse, failed applications, and a bad taste with many project managers (who tend to have long memories...). Part of the problem might also be due to the lack of adequate software tools to develop and safely implement chemometric models in a process analytical environment. Finally, some of the shortfall might simply be due to lack of qualified resources to develop and maintain chemometrics-based analytical methods in the field. 

In practice, the applicability of ELECTRE methods is also limited by the lack of commercial software packages. The software tools available are academic developments by the team around Bernard Roy from LAMSADE (cf. Weistroffer et al. 2005)... 

Software tools are applied in every step of process development. Tools for individual reactor simulations such as computational fluid dynamic simulations are not the topic in this chapter. These tools supply only numerical data for specific defined reactor geometry and defined specific process conditions. A change of parameter would demand a complete recalculation, which is often a very time-consuming process and not applicable to a parameter screening. Methods for reactor optimization by CFD are described in detail in the first volume of this series. Tools for process simulation allow the early selection of feasible process routes from a large... 

The SRC program KOWWIN uses an atom/fragment contribution method to predict log Kow. This is a reductionist method (the fragment coefficients were derived by multiple regression from a development set of reliably measured log Kow values). The other main software tool, ClogP for Windows (Leo, 1993) is a constructionist method (the fragment coefficients are evaluated from the simplest examples in which they occur). Both methods have a high level of accuracy and are widely accepted as the best tools available. 

The fit of the experimental data to the developed model is done by varying the equilibrium constants and one rate constant, until the best possible fit is obtained by minimizing the least square method (the most commonly applied method). Such fitting can be done with a variety of simulation software tools. 

The rapid development of computer technology has yielded powerful tools that make it possible for modem EIS analysis software not only to optimize an equivalent circuit, but also to produce much more reliable system parameters. For most EIS data analysis software, a non-linear least squares fitting method, developed by Marquardt and Levenberg, is commonly used. The NLLS Levenberg-Marquardt algorithm has become the basic engine of several data analysis programs. 

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