[Quantitative determination of crystallin insulin in insulin-zinc suspensions as an in-process control].

A method is described for the quantitative determination of amorphous and crystalline insulin contents in insulin zinc suspensions. The different resolving rates of the modifications in acid dilutions are utilized for the test. Measurements are made by UV spectroscopy. Information is given on the application of this method for the analysis of the course of insulin crystallization and it is compared with the USP XXI method.