Recognition of Limonene volatile using Interdigitated Electrode molecular imprinted polymer sensor

Abstract

Limonene is a type of terpene hydrocarbons commonly produced by plants and known to possess a strong smell of oranges. Electronic nose (e-nose) is an artificial olfaction device that is able to replicate the human olfactory sense. By using Interdigitated Electrode (IDE) structure, an e- nose sensor for detecting Limonene volatile by using molecular imprinted polymer (MIP) was fabricated. The MIP membrane contained the methacrylic acid, which formed specific cavities originated by target molecule. The ingredients for MIP were then polymerized on the surface of IDE with PET as substrate which is low in cost. The sensing property was examined in gas phase for evaluate the sensor sensitivity and selectivity. The IDE MIP sensor is capable to detect Limonene contained gas. The sensor characteristics were strongly influenced by the composition ratio of cross- linker, functional monomer and template molecule. The remained molecule on MIP can be removed by immersing thus the sensor can be used repeatedly. By determining Limonene volatile released during pre-matured until matured period, one could use this as a data point to determine certain fruit maturity. Apart from monitoring fruit maturity, this sensor can also be use for those who have respiratory allergy towards Limonene where most reported cases of irritation have involved long-term industrial exposure to the pure compound, e.g. during degreasing or the preparation of paints.