Sample throughput optimization

LC/MS analyses requiring high resolving power to separate all compounds present in a sample may be optimized as well to increase throughput. Optimizing in the LC dimension utilizes smaller particles as well more radical approaches may involve a change in workflow toward extremely high column efficiencies and peak capacities in contrast to the present common work flow of many individual runs with modified selectivities. 

If the excipients do not interfere with the CE separation, the available drug substance method can also be applied to the drug product without further optimization. This is the most favorable option. Each additional sample preparation step decreases the sample throughput speed, increases the variability of the method, and requires more validation effort. Fortunately CE is a high-efficiency method and interference of excipient peaks with analyte peaks occurs rarely. 

Optimization of the RP HPLC system is critical for maximum sample throughput compatible with the mass spectrometer data acquisition capabilities. For highest throughput, the samples should be injected into the HPLC column or directly into the mass spectrometer using the overlay method, i.e., during the ESI-MS assay of a sample, the next sample is retrieved and prepared for injection immediately... 

Dunn-Meynell, K W. Wainhaus, S. Korfmacher, W. A. Optimizing an ultrafast generic high-performance liquid chromatography/tandem mass spectrometry method for faster discovery pharmacokinetic sample throughput. Rapid Commun Mass Spectrom 2005, 19, 2905-2910. 

The innovative use of bioassays based on biological molecules such as antibodies is changing the way analysts approach many traditional problems. The current tendency within residue analysis is toward the development of either fast screening procedures that are optimized for maximum sample throughput and a minimum chance of obtaining false-negative results, or confirmatory methods. 

As a compromise between sampling rate and analytical sensitivity, an injection volume of 300 iL and a flow rate of 2.1 mL mur1 are chosen. With this optimized system a sampling throughput of 55 h 1 is attained for... 

Phenol and the three dihydroxybenzenes (20, 42, 66) in water were determined by LLE with a hydrophilic solvent followed by amperometric titration. LOD was in the ppm range . A dual electrode in a FIA system has been used as detector for total phenols in wastewater. The upstream coulometric electrode has a large surface area and is used to eliminate compounds that cause interference and the second one is an amperometric electrode for oxidative detection of all phenols. Optimal results were found working with a phosphate buffer at pH 6.8, at potentials of +0.35 V and +0.78 V for the coulometric and amperometric electrodes, respectively. A high sample throughput of 60 per hour can be attained with RSD of 0.1-4%. This method is more reliable than the colorimetric method . The concentration of fenobucarb (142) in drinking water was determined after a short alkaline hydrolysis, and oxidation of the resulting 2-s-butylphenol with a GCE at 750 mV, pH 3.5 LOD was 3.6 x 1Q- M, RSD 3.74% for 1 x IQ- M (n = 11, p = 0.05)37 . 

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