Protein precipitation screening study

Table 4 Design Table for Protein Precipitation Screening Study (2 Full Factorial Experimental Design with Center Point)...

Among the possible limitations for the use of NMR as a screening tool, the relative insensitivity of NMR as compared with other spectroscopical methods is the more important. This fact imposes the use of high total compound concentration for the ligand molecules and limits the mixture size that can be tested because of compound solubility, protein precipitation and non-specific binding. We shall see in several examples that this limitation turns out to be inherently less important as the use of new probes and higher fields become available, lowering the threshold of sample concentration to be used in these studies. 

The post-colunm infusion setup has been widely applied in matrix effects studies, e.g., in developing methods for the quantitative screening of drag discovery compoimds by fast-gradient (1 min ran time) LC-MS [83-85], in the optimization of the sample pretreatment in the analysis of methadone, comparing four off-hne and three on-hne sample pretreatment methods [77], and in evaluating various protein precipitating additives [86],... 

The information obtained from the screening studies provided us with the direction to take for a larger qualification study. It was clear from a scientific standpoint that heat inactivation of a protein solution generates some protein aggregates. The subsequent precipitation step purifies the... 

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