Chitosan Coating on Quartz Crystal Microbalance Gas Sensor for Isopropyl Alcohol and Acetone Detection

Abstract

The development of acoustic wave sensors was driven by the presence of modern technology. Quartzcrystal microbalance (QCM) has excellent sensing capabilitiesand has wide range ofapplications. Selection of sensing layer is crucial to ensure the performance of the QCM sensor for volatile organic compound (VOC) detection. Hence, the objective of this paper is to compare the performance of chitosan coated QCM sensor for different analyte gas: isopropyl alcohol (IPA). Finite element simulation was implemented usingCOMSOL Multiphysics to study the resonance frequency shift before and after sensing. Simulation results shows IPA detection shows a higher resonance frequency shift of 62.5 Hzcompared to acetone due to higher molar mass. Experimental work is conducted to validate the simulation results where IPA analyte gas yields in 84.8 Hz which is higher than acetone analyte gas at 41.8 Hz. The functional groups for both sensing layer and analyte gas also affects the gas detection performance. IPA analyte gas possessed hydroxyl groups that favors to hydrogen bond formation with chitosan sensing layer. Thus, the QCM sensor with chitosan as the sensing layer has the potential for VOC sensing of different molar mass and functional groups.

Acetone Detection and Classification as Biomarker of Diabetes Mellitus Using a Quartz Crystal Microbalance Gas Sensor Array

“…When our sensors are compared with other ones in which an organic sensing film was employed, we found very good performance using our devices. For instance a chitosan sensing film achieved S Ace = 0.0240 Hz/ppm and S iPrOH = 0.0493 Hz/ppm, a metal organic framework achieved S Ace = 0.0008 Hz/ppm, and nanostructure-modified materials achieved S Ace = 0.00003 Hz/ppm, which are smaller than the values achieved by our devices [45][46][47]. Even though our sensitivities are high, the results suggest that it is necessary to increase the sensitivity of gas sensor arrays in order to be able to quantify lower concentrations, especially for Ace.…”

“…than the values achieved by our devices [45][46][47]. Even though our sensitivities are high, the results suggest that it is necessary to increase the sensitivity of gas sensor arrays in order to be able to quantify lower concentrations, especially for Ace.…”