{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,27]],"date-time":"2026-09-27T21:39:46Z","timestamp":1790545186214,"version":"4.1.0"},"reference-count":22,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2019,11,23]],"date-time":"2019-11-23T00:00:00Z","timestamp":1574467200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000780","name":"European Commission","doi-asserted-by":"publisher","award":["LIFE17 ENV\/FR\/000330"],"award-info":[{"award-number":["LIFE17 ENV\/FR\/000330"]}],"id":[{"id":"10.13039\/501100000780","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Micromachines"],"abstract":"<jats:p>This paper describes a compact microfluidic analytical device developed for the detection of low airborne formaldehyde concentrations. This microdevice was based on a three-step analysis, i.e., the passive gaseous formaldehyde uptake using a microporous membrane into an acetylacetone solution, the derivatization with acetylacetone to form 3,5-diacetyl-1,4-dihydrolutidine, and the quantification of the latter using fluorescence detection. For a rapid and easier implementation, a cylindrical geometry of the microporous element was considered to perform laboratory-controlled experiments with known formaldehyde concentrations and to establish the proof of concept. This work reports the evaluation of the uptake performance according to the microporous tube length, the liquid flow rate inside the tube, the gas flow rate outside the tube, and the gaseous formaldehyde concentration. A 10.0 cm microporous tube combined with a gas flow rate of 250 NmL\/min (normal milliliters per minute) and a liquid flow rate of 17 \u00b5L\/min were found to be the optimized conditions. In these experimental conditions, the fluorescence signal increased linearly with the gaseous formaldehyde concentration in the range 0\u2013118 \u00b5g\/m3, with the detection limit being estimated as 0.13 \u00b5g\/m3 when considering a signal-to-noise ratio of 3.<\/jats:p>","DOI":"10.3390\/mi10120807","type":"journal-article","created":{"date-parts":[[2019,11,25]],"date-time":"2019-11-25T03:10:00Z","timestamp":1574651400000},"page":"807","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Development and Optimization of an Airborne Formaldehyde Microfluidic Analytical Device Based on Passive Uptake through a Microporous Tube"],"prefix":"10.3390","volume":"10","author":[{"given":"Ana\u00efs","family":"Becker","sequence":"first","affiliation":[{"name":"Universit\u00e9 de Strasbourg, CNRS, ICPEES UMR 7515, F-67000 Strasbourg, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Christina","family":"Andrikopoulou","sequence":"additional","affiliation":[{"name":"Universit\u00e9 de Strasbourg, CNRS, ICPEES UMR 7515, F-67000 Strasbourg, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pierre","family":"Bernhardt","sequence":"additional","affiliation":[{"name":"In\u2019Air Solutions, 25 rue Becquerel 67087 Strasbourg, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ruben","family":"Ocampo-Torres","sequence":"additional","affiliation":[{"name":"Universit\u00e9 de Strasbourg, CNRS, ICPEES UMR 7515, F-67000 Strasbourg, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Claire","family":"Trocquet","sequence":"additional","affiliation":[{"name":"In\u2019Air Solutions, 25 rue Becquerel 67087 Strasbourg, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"St\u00e9phane","family":"Le Calv\u00e9","sequence":"additional","affiliation":[{"name":"Universit\u00e9 de Strasbourg, CNRS, ICPEES UMR 7515, F-67000 Strasbourg, France"},{"name":"In\u2019Air Solutions, 25 rue Becquerel 67087 Strasbourg, France"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2019,11,23]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2424","DOI":"10.1016\/j.atmosenv.2007.12.017","article-title":"Air change rate and concentration of formaldehyde in residential indoor air","volume":"10","author":"Gilbert","year":"2008","journal-title":"Atmos. Environ."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"2536","DOI":"10.1021\/cr800399g","article-title":"Formaldehyde in the Indoor Environment","volume":"110","author":"Salthammer","year":"2010","journal-title":"Chem. Rev."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"2851","DOI":"10.1016\/j.atmosenv.2006.11.039","article-title":"Characteristics of carbonyls: Concentrations and source strengths for indoor and outdoor residential microenvironments in China","volume":"13","author":"Wang","year":"2007","journal-title":"Atmos. Environ."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"2074","DOI":"10.1016\/j.atmosenv.2010.03.023","article-title":"Ambient formaldehyde and its contributing factor to ozone and OH radical in a rural area","volume":"44","author":"Xiaoyan","year":"2010","journal-title":"Atmos. Environ."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"1344","DOI":"10.1111\/j.1398-9995.2006.01174.x","article-title":"Inhaled formaldehyde exposure: effect on bronchial response to mite allergen in sensitized asthma patients","volume":"61","author":"Casset","year":"2006","journal-title":"Allergy"},{"key":"ref_6","unstructured":"(2004). IARC Overall evalutation of carcinogenicity to humans, formaldehyde. Oncol. Times, 26, 72."},{"key":"ref_7","unstructured":"(2019, November 22). ANSES - Agence nationale de s\u00e9curit\u00e9 sanitaire de l\u2019alimentation, de l\u2019environnement et du travail Valeurs Guides de qualit\u00e9 d\u2019Air Int\u00e9rieur (VGAI) Le formald\u00e9hyde. Available online: https:\/\/www.anses.fr\/fr\/system\/files\/AIR2017SA0041Ra.pdf."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"195","DOI":"10.1016\/1010-6030(93)80117-R","article-title":"Photophysical properties of 3,5-diacetyl-1,4-dihydrolutidine in solution: application to the analysis of formaldehyde","volume":"74","author":"Salthammer","year":"1993","journal-title":"J. Photochem. Photobiol. A Chem."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"1821","DOI":"10.5194\/acp-10-1821-2010","article-title":"Sample drying to improve HCHO measurements by PTR-MS instruments: laboratory and field measurements","volume":"10","author":"Jobson","year":"2010","journal-title":"Atmos. Chem. Phys."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"5768","DOI":"10.1016\/j.atmosenv.2006.05.017","article-title":"Formaldehyde measurements in libraries: Comparison between infrared diode laser spectroscopy and a DNPH-derivatization method","volume":"40","author":"Hanoune","year":"2006","journal-title":"Atmos. Environ."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"1055","DOI":"10.5194\/amt-3-1055-2010","article-title":"Formaldehyde measurements by Proton transfer reaction \u2013 Mass Spectrometry (PTR-MS): correction for humidity effects","volume":"3","author":"Vlasenko","year":"2010","journal-title":"Atmos. Meas. Tech."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"2754","DOI":"10.1039\/C6LC90070D","article-title":"Microfluidic fuel cells for energy generation","volume":"16","author":"Safdar","year":"2016","journal-title":"Lab. Chip."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"13360","DOI":"10.1021\/ja020932y","article-title":"Efficient Mixing and Reactions within Microfluidic Channels Using Microbead-Supported Catalysts","volume":"124","author":"Seong","year":"2002","journal-title":"J. Am. Chem. Soc."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"102","DOI":"10.1016\/j.talanta.2017.05.038","article-title":"On-line gaseous formaldehyde detection by a microfluidic analytical method based on simultaneous uptake and derivatization in a temperature controlled annular flow","volume":"172","author":"Guglielmino","year":"2017","journal-title":"Talanta"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"1462","DOI":"10.1039\/c2em10935b","article-title":"Mobile monitoring along a street canyon and stationary forest air monitoring of formaldehyde by means of a micro-gas analysis system","volume":"14","author":"Toda","year":"2012","journal-title":"J. Environ. Monit."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"551","DOI":"10.1016\/j.snb.2013.02.043","article-title":"Transportable, fast and high sensitive near real-time analyzers: Formaldehyde detection","volume":"181","author":"Allouch","year":"2013","journal-title":"Sensors Actuators B Chem."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1021\/cr60275a001","article-title":"Chemistry of dihydropyridines","volume":"72","author":"Eisner","year":"1972","journal-title":"Chem. Rev."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"1336","DOI":"10.1016\/j.atmosenv.2005.10.027","article-title":"Aldehyde measurements in indoor environments in Strasbourg (France)","volume":"40","author":"Marchand","year":"2006","journal-title":"Atmos. Environ."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"63","DOI":"10.1016\/j.atmosenv.2006.08.008","article-title":"Diurnal and seasonal trends in carbonyl levels in a semi-urban coastal site in the Gulf of Campeche, Mexico","volume":"41","author":"Muriel","year":"2007","journal-title":"Atmos. Environ."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"151","DOI":"10.1016\/j.atmosenv.2015.05.004","article-title":"Seasonal variations of outdoor air pollution and factors driving them in the school environment in rural Bhutan","volume":"113","author":"Wangchuk","year":"2015","journal-title":"Atmos. Environ."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"2991","DOI":"10.1016\/j.atmosenv.2010.05.044","article-title":"Henry\u2019s law constant measurements for formaldehyde and benzaldehyde as a function of temperature and water composition","volume":"45","author":"Allou","year":"2011","journal-title":"Atmos. Environ."},{"key":"ref_22","unstructured":"Le Calv\u00e9, S., Andrikopoulou, C., Becker, A., Bernhardt, P., and Trocquet, C. (2019). Proc\u00e9d\u00e9 et dispositif d\u2019analyse microfluidique pour la quantification de polluants gazeux solubles dans l\u2019eau. (n\u00b0 1906855), French patent, submitted on June 25."}],"container-title":["Micromachines"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2072-666X\/10\/12\/807\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T13:36:55Z","timestamp":1760189815000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2072-666X\/10\/12\/807"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2019,11,23]]},"references-count":22,"journal-issue":{"issue":"12","published-online":{"date-parts":[[2019,12]]}},"alternative-id":["mi10120807"],"URL":"https:\/\/doi.org\/10.3390\/mi10120807","relation":{},"ISSN":["2072-666X"],"issn-type":[{"value":"2072-666X","type":"electronic"}],"subject":[],"published":{"date-parts":[[2019,11,23]]}}}