Determining Estragole (4-allylanisole) Vapor of Essential Oil Using Polymer Membranes, ATR-FTIR Spectroscopy, and QCM

Background: The adsorption of volatile estragole vapor by various polymer membranes was determined using attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy and quartz crystal microbalance (QCM) gas sensor data. Methods: The estragole gas exposure adsorption experiments were selected based on polymer membrane properties: density, double bond saturation, polarity, etc. Results: Correlation coefficients for ATR-FTIR and QCM were 0.9887 at 1510 cm-1, 0.9991 at 1242 cm-1, and 0.9896 at 1035 cm-1. Compared with QCM, ATR-FTIR spectroscopy nondestructive, faster, less expensive, and sufficiently sensitive that it can be used to analyze gas adsorption on a membrane when measuring the estragole content of essential oils; thus, ATR-FTIR is a practical method for assessing fragrance vapor in essential oils. Conclusion: ATR-FTIR and QCM are comparable nondestructive analytical methods for detecting vapor and gas, but ATR-FTIR is faster and less expensive.