2005 Volume 54 Issue 7 Pages 613-619
In this study, we examined a separation analysis method for amino modifier silicones (AMS) and dimethylsilicones (DMS) in hair rinses. Generally, size-exclusion chromatography (SEC) is used for the analysis of silicones. However, SEC cannot separate AMS and DMS by the size-exclusion principle only when the molecular weights are nearly the same. Therefore, we examined the derivatization method of AMS and a separation method for AMS and DMS by SEC-UV-RI (SEC with an ultraviolet detector and a refractive index detector). After an analysis, we were able to detect and determine only the amount of AMS by the derivatization of AMS with N -succinimidyl 4-nitorophenylacetate (SNPA) by using UV (280 nm), and were also able to determine the total silicone (AMS and DMS) amounts by using RI. In addition, the DMS amount was given by subtracting the AMS amount from the total silicone amounts. The recovery rates from model hair rinses were good, and the results were reproducible, except for a portion. Moreover, the chromatograms and molecular weights were in good agreement with the raw materials. In addition, we established a method for calculating the modified rates of AMS by using the analysis method described above.
