Advanced automated sample processing

The determination of lead in blood is the most widespread clinical use of ASV The technique is attractive because it is rapid, simple and reproducible A recent advance is to couple ASV to flow injection analysis in order to automate the process so that smaller samples and shorter analysis time can be achieved Lead is also routinely determined in bonemeal meant for human consumption by ASV Both lead and cadmium are determined in agricultural crops by ASV... 

The analysis of phytochemicals is a tedious process involving several steps in which care must be taken to avoid degradation and contamination. Recent advancements in extraction, concentration, purification and analytical procedures of phytochemicals have been made, but additional developments are needed to assist in the identification and quantification of the diverse array of phytochemicals present in plants and foods, as well as metabolites in biological samples. Specifically there is a need to automate sample extraction, clean-up, and concentration steps to facilitate the screening of phytochemicals develop analytical methods with improved sensitivity, resolution and throughput that utilize less organic solvents and develop concentration and purification methods to produce analytical standards that are not available commercially. Continued advancements in sample preparation and analytical techniques will assist researchers in their quest to identify and quantify the vast array of phytochemicals present in plants... 

The automated radiochemical process is performed in a single functional unit. The instrument design incorporates advanced digital fluid handling techniques with multiple zero dead volume digital syringe pumps and multiple valves for sample and reagent delivery. Comprehensive multithreaded control software was... 

In addition to these qualitative studies, quantitative bioanalysis, e.g., in preclinical and clinical studies to provide pharmacokinetic and pharmacodynamic data, is an essential part of drug development. Quantitative bioanalysis is the most important application area of LC-MS, in terms of number of instruments applied and the number of analyses performed. Fast, high-throughput, and routine quantitative analysis by LC-MS also demands fast and automated sample pretreatment strategies and advanced data-processing software. 

Sample Preparation Normally, biological samples are not directly compatible with LC-MS/MS analysis, and they need to be processed before delivery to the LC-MS system. Effective sample preparation procedures can clean up the sample and concentrate the analytes of interest. Conventional sample preparation is often the most labor-intensive and time-consuming step in a liquid chromatography-tandem mass spectrometry (LC-MS/MS) analytical method. Introduction of automated 96-well extraction techniques, and advances in sample preparation techniques, have greatly improved the efficiency of sample preparation. 

Accelerated solvent extraction (ASE) is a relatively recent advance in sample preparation for trace environmental analysis. This techiuque uses conventional solvents at elevated pressures and temperatures to extract solid samples quickly. The process takes advantage of the increased analyte solubilities at temperatures well above the boiling points of common solvents. Under these conditions, the kinetic processes for the desorption of analytes from the matrix are accelerated. Currently a commercial unit is available in which automated extractions can be carried out on 24 samples sequentially (Richter et al., 1995, 1996). This technique offers some significant advantages over SEE and MAP. SEE uses supercritical CO2, which is a nonpolar fluid, whereas MAP requires the presence of a polar solvent that couples with microwave to promote heating. By comparison, ASE uses the same solvent as traditional Soxhlet extractions, which means a (firect transfer of methodology is feasible without any of the restrictions or limitations of the two other methods. Method development time is therefore shortened. 

The study by Chalcraft et al. suggests furthermore that with a refined computational prediction of ionization efficiencies from chemical structure or available physicochemical parameters some progress could be made towards a (semi)quanti-tative analysis of unknowns and suspects without reference standards (Chalcraft et al. 2009). To enable a non-target screening of environmental samples with several thousand peaks within a reasonable time frame, advanced software solutions are needed with capabilities for automated batch processing and fast database queries. At the moment, integration within handy workflows of software packages is mainly available in the field of metabolomics, which is only partly applicable to environmental samples. 

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