Analysis of Acetylated Hyaluronic Acid in Moisturizing Lotion and Milk Lotion by HPLC with Fluorescence Detection

We developed a simple and sensitive analytical HPLC method for the determination of acetylated hyaluronic acid (AcHA) in moisturizing and milk lotions. AcHA with different molecular weights was separated as a single peak using a C4 column and detected through post-column derivatization using 2-cyanoacetamide. The limits of detection and quantification were 60 and 200 ng, respectively. We found that AcHA in water was successfully extracted into a strong anion exchange (SAX) spin column with a recovery rate of AcHA was 63.8 ± 1.8%. Although the supernatant from acetone precipitation of lotions could pass through the spin column, the recovery rate (%) and accuracy of AcHA were affected by the viscous properties of cosmetics and acidic and acetone-soluble ingredients. Upon conducting analytical methods in this study, the concentration of AcHA in nine lotions was found to have ranged from 7.50 to 83.3 µg/mL. These values are comparable to the concentration range of AcHA in emulsions that have been previously evaluated for their superior effects. We believe that the analytical and extraction method is useful for the qualitative analysis of AcHA in moisturizing and milk lotions.