Development of microfluidic analytical method for on-line gaseous Formaldehyde detection

Abstract

Highlights • Novel analytical micro-device for quantification of gaseous formaldehyde • Gaseous Formaldehyde uptake through the establishment of a microfluidic annular flow • Formaldehyde detection using colorimetric cell using a liquid-core-waveguide

Near Real-Time Monitoring of Formaldehyde in a Low-Energy School Building

“…The objectives of this study are two-fold: firstly, to provide experimental data on the temporal variations of aldehydes concentrations in a Low-Energy building, and secondly, to test, under real conditions, a new formaldehyde analyzer which has already been validated by previous laboratory studies [17,18]. Therefore, this work reports formaldehyde and aldehydes measurements in indoor air for two weeks during the MERMAID intensive field campaign performed in a junior high school recently built according to the French thermal regulation of 2005.…”

“…The analytical method recently developed in our laboratory was already detailed in our previous studies [17,18]. As shown in Figure 1, this analytical method is also based on three highly coupled steps: (1) the uptake of gaseous formaldehyde into an aqueous acetylacetone solution at room temperature;…”

“…Air is sampled at 20 mL min −1 by a mass flow controller (IQ+Flow, Bronkhorst) combined to a mini air pump (270 EC, Schwarzer) to maintain a stable gas flow injected coaxially into the capillary of 150 cm long and 530 µm ID. At the same time, the aqueous acetylacetone liquid solution prepared according to the same procedure mentioned above is continuously injected at 17 µL min −1 by a micro peristaltic pump through a specific Tee into the same capillary [17,18]. The coinjection of both the gas mixture and the aqueous acetylacetone solution into the capillary (see Figure S3) permits a diphasic flow to be obtained.…”

“…The coinjection of both the gas mixture and the aqueous acetylacetone solution into the capillary (see Figure S3) permits a diphasic flow to be obtained. Depending on gas and liquid flows ratio, three different flow regimes can be obtained: bubble, slug, and annular flow [17,18,37]. Guglielmino et al (2017aGuglielmino et al ( , 2017b have shown that the annular flow allows the improvement of the uptake of gaseous formaldehyde into the acetylacetone solution leading to an uptake yield of about 90-100%.…”

“…Although the pollution levels in conventional buildings have been largely studied, in particular, in France, with the large-scale investigations by the French indoor air quality observatory (OQAI) [2], not much is known about the indoor air quality of low-energy buildings, be it private dwellings [3] or [26] Acetyl acetone + fluorescence (1st generation of formaldehyde analyser) 0.5 (S/N = 3) 6-10 min None identified 1100 6 8 2 [30] Acetyl acetone + Colorimetric microfluidic device 0.7 (S/N = 3) 1-2 min None identified 35 9 8 [17,18] Acetyl acetone + Fluorimetric microfluidic device 1.2 (S/N = 3) 2 s None identified 20 4 This work N/A: Information not available; 1 DNPH: 2,4-dinitrophenylhydrazine and HPLC/UV-vis: High-Performance Liquid Chromatography coupled to UV-visible detection; 2 It corresponds only to the instrument weight and does not refer to the total weight of the operating system, i.e., it does not include any liquid reagents reservoir or gas cylinder; 3 GC-MS: Gas Chromatography coupled to Mass Spectrometer; 4 FTIR: Fourier-transform infrared spectroscopy; 5 PTR/MS: Proton-transfer-reaction mass spectrometry 6 Two reagents are needed; 7 Three reagents are involved; 8 The deuterium lamp DH-2000 (Ocean Optics) weighs 5.5 kg whereas the microfluidic device is around 3.5 kg including its electronic part.…”