Automated method development/optimization

QuanOptimize from Micromass also allows automated method development for quantitative LC/MS/MS. It automatically identifies the best method for each compound, then runs batches of samples for quantitative analyses and report results in a QuanLynx browser. Thermo recently launched a similar product for automatic MS tuning. Known as QuickQuan, it generates data and stores it in a central Microsoft Access or Oracle database for future access. The infusion-based valve switching auto-tuning device allows individual compounds to be fully and automatically optimized in about 1 min. 

Recently there has been renewed interest in automated method development in which the optimization software directly interfaces with the instrument in order to run or suggest new experiments based on the prior results that generated the initial resolution maps. In the late 1980s, a number of approaches to this problem were attempted, but none of these tools prevailed, due in part to the challenges of tracking peaks between experiments. 

All approaches to method optimization based on multiple experiments have the requirement that all components be detected and that they be tracked between runs. For complex samples, this is typically the most labor-intensive aspect of method development. For unattended method development, the instrument is required to monitor the change in retention of each component automatically. The historical limitations to this technology have been a key stumbling block in the widespread adoption of automated method development. 

The method development process for on-line SPE is ideal for its ability to offer full automation. Method development involves the examination of several extraction variables with subsequent optimization. These parameters include the sorbent chemistry, the composition of the load, wash and elution solvents, sorbent particle size, solvent volumes, and flow rates. A general overview of the method development process for on-line SPE coupled to LC... 

Traditional, and perhaps, manual approaches for method development would be too time-consuming to perform within a drug discovery environment. As a result, automated method development routines, such as the procedure to generate optimized SRM tables for PK screening, are an essential requirement for drug discovery support [60],... 

A general flow chart for partly automated method development is presented in Fig. 2. From this, it is clear that the analyst repeatedly intervenes in order to evaluate intermediate results to steer the direction of development At the outset, according to the available information as well as the experience of the analyst, the chromatographic factors that are to be examined are defined and their limits are delineated. Thereafter, the HPLC system takes over the execution of the necessary experiments and/or the chromatographic runs. The analyst evaluates the runs once they have finished. The number of peaks, and their form, resolution, and sequence are important. As a result, conditions can be hypothesized that should have the highest potential for optimal separation of all of the peaks, or at least of all the relevant ones. 

There are several software and automated systems for HPLC method development and optimization, such as Drylab , Chromsword , and ACD/AutoChrom MDS, and others (43 7). Their principles can be applied to UHPLC. In addition. Waters Corp. (Milford, MA) has recently promoted Fusion Method Development software. Fusion Method Development software from S-Matrix integrates seamlessly with Water s ACQUITY UPLC and Empower 2 Chromatography software to automate method development. The software automatically generates instrument methods and sample sets. Another feature of this software is to visualize data by statistically fitting the results. However, it cannot generate simulated chromatograms at predicted conditions, like Drylab can. 

Method development remains the most challenging aspect of chiral chromatographic analysis, and the need for rapid method development is particularly acute in the pharmaceutical industry. To complicate matters, even structurally similar compounds may not be resolved under the same chromatographic conditions, or even on the same CSP. Rapid column equilibration in SFC speeds the column screening process, and automated systems accommodating multiple CSPs and modifiers now permit unattended method optimization in SFC [36]. Because more compounds are likely to be resolved with a single set of parameters in SFC than in LC, the analyst stands a greater chance of success on the first try in SFC [37]. The increased resolution obtained in SFC may also reduce the number of columns that must be evaluated to achieve the desired separation. 

Integrating chemical analysis methods and physical sensors with microreactors enables monitoring of reaction conditions and composition. This ability renders instrumented microreactors powerful tools for determining chemical kinetics and identifying optimal conditions for chemical reactions. The latter can be achieved by automated feedback-controlled optimization of reaction conditions, which greatly reduces time and materials costs associated with the development of chemical synthesis procedures. 

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. 

The method development process will be aided if we are able to use sophisticated instrumentation (see also section 1.7.2). Automated injection and data handling will allow a number of experiments to be performed without the requirement of an analyst being present. Moreover, we have seen in chapter 5 (section 5.6) that the use of sophisticated detection techniques (dual-channel or multi-channel detectors) may be of help in the optimization process. 

Moreover, once a particular column or columns that have provided the best selectivity are chosen, an automated method optimization may be performed. This would include employment of an integrated HPLC method development system such as AMDS/Drylab such that the gradient slope/temperature... 

The advantages of on-line automation are the achievement of time savings in relation to the chromatographic method development time. The software can make decisions at any time of the day or night and can immediately communicate this information to the instrument after the completion of the experiment. There is also a more subtle benefit to the link of optimization software to the chromatography data system. Method development wizards with drop-down menus/user-defined fields can simplify the process of configuring the instrument sequence/method prior to a method development session. 

Advantages. This is critical technology to enable both automated and routine application of computer-assisted optimization. The manual effort required for traditional approaches to data interpretation in chromatographic method development is quite considerable. 

Due to the intended use of late-phase methods, the methods should be optimized to be as rapid and simple as possible while meeting the specified requirements. Considerations in method development should include the ability to fully automate sample preparation and to ensure that the methods are sufficiently rugged and robust to allow for transfer to other laboratories. 

Method development to provide robust analyte-specific procedures from complex biomatrices has received significant attention. Modular on-line and off-line approaches have been reported that focus on a systematic and integrated approach to select optimal extraction and separation chemistries [27]. These approaches have automated data analysis, whereby the feedback loop from experimentation to decision can be significantly reduced [18]. Wells has comprehensively discussed the use of automated strategies for the rapid determination of optimal extraction chemistries to maximize analyte recovery and selectivity [28]. The book includes up-to-date information on available robotic platforms for automated sample preparation and comprehensive information on labware. 

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