Volatile Organic Compounds (VOCs) are substances which were proved to be harmful for the human health. People are spending about 90% of their time indoors where these chemicals are present in high concentrations [1]. Among VOCs, formaldehyde is a major pollutant due to multiple indoor pollution sources (furniture, paintings, etc.) and high degree of toxicity being classified internationally as carcinogenic. Starting from the necessity of real time measurement of formaldehyde concentration, a device has already been developed by both ICPEES and In'AirSolutions in Strasbourg [2] which was proved to be sensitive and portable. The analyzer works following three main stages. In the first stage, an annular two-phase flow is established in order to trap gaseous formaldehyde into an aqueous solution containing a chemical reagent. In the second stage, the kinetics of the reaction between formaldehyde and reagent are accelerated inside an oven at a specific temperature. Resulted chemical reaction product is a fluorescent compound and its concentration is measured inside a fluorescent cell, in the third stage of the process. Separation techniques using two-phase flows in micro-and mini-channels turned to be much more interesting since the increasing scientific interest in the fields of microfluidics and microfabrication techniques registered a consistent advancement. Among all applications of microfluidic separation, utilization of this technique for identification of air pollutant concentrations is very important due to its high miniaturization potential. For being capable of promoting merchandisable micro-separation systems, it is necessary to develop microsystems working in stabilized and reproducible conditions. This work is part of a common effort for improving and miniaturizing the capabilities of this existing formaldehyde analyzer to integrate it into a real time miniaturized, ultra-portable, autonomous and reliable formaldehyde measurement system. More precisely, two areas for improvement have been identified. On one hand, a new approach for improving the uptake yield of the gaseous formaldehyde has to be proposed in order to diminish the response time and the liquid reagent consumption. On the other hand, the current fluorescent