Polyethyleneimine-modified quartz crystal microbalance and its characteristics for detecting acetic acid

Acetic acid is a clear liquid with a strong smell of acids. The danger of inhaling acetic acid vapors may cause irritation of the nose and throat. At high vapor levels, acetic acid may cause respiratory inflammation and can cause eye irritation and eye damage permanently. New detection methods of acetic acid are urgently required especially for practical applications. In this study, the acetic acid vapor sensor was developed by depositing polyethyleneimine (PEI) layer onto the two QCM substrates using well-known self-assembled monolayers (SAM) method. As results, the sensor was less sensitive to humidity. The sensor also showed high sensitivity and limit of detection limit (0.85 mg/L) to acetic acid. © 2019 Trans Tech Publications Ltd, Switzerland.