Determination of active content

The active content of acyl isethionates in raw materials and products is determined either by titration with benzethonium chloride or by saponification. The fatty acid may be extracted after acidification for molecular- 

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In many pharmaceutical companies, quality control departments already use NIRS to identify formulations. Figure 23 illustrates a PLS calibration for the active content determination in a low-dose tablet. Once identity testing is passed, it is straightforward to consider as a next step the determination of active content in intact tablets. Thus, qualitative and quantitative analysis can be performed by acquiring a single NIR spectrum per sample. Two analytical techniques are replaced by one—nondestructive—NIR measurement. For this purpose near-infrared spectroscopy is a fast and powerful alternative to traditional analysis, which only remains necessary as reference analytics. 

As noted earlier, the reaction is very sensitive to the presence of contaminating proteins and other compounds. Also arylsulfatase A is competitively inhibited by many anions such as phosphate (Ki = 0.6 mM [Gniot-Szulzycka, 1974]), sulfate, and others. Precise determination of activator content with this method is therefore very difficult. 

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