Prototyping a miniaturized microfluidic sensor for real-time detection of airborne formaldehyde

Abstract : Formaldehyde is a carcinogenic volatile organic compound that is largely used in the fabrication process of a variety of household products, being sometimes released indoor in concentrations that are beyond the limits recommended by the World Health Organization. The current commercially available formaldehyde sensors are far from simultaneously being ultra-portable, highly sensitive (< 1 ppb), real-time, and especially cost-efficient. This work aims to study the feasibility to miniaturize the formaldehyde sensing system down to a palm hand device, based on the microfluidic Hantzsch reaction method and fluorescence detection. A Gas-Liquid Micro-Reactor based on integration of a hydrophobic membrane inside a polymer flat chip is proposed and its formaldehyde trapping yield is planned to be further tested. By combining contact sensing with time-resolved CMOS sensors, the dimensions of the fluorescence detection component could go down to 10 mm × 20 mm × 30 mm by using commercialavailable components and therefore, enabling continuous and fast-response measurements using small volumes and low concentration samples.