Sensors and Actuators B 181 (2013) 551–558 Contents lists available at SciVerse ScienceDirect Sensors and Actuators B: Chemical journa l h o mepage: www.elsevier.com/locate/snb Review Transportable, fast and high sensitive near real-time analyzers: Formaldehyde detection Alaa Allouch a,b,∗ , Maud Guglielmino a , Pierre Bernhardt a , Christophe A. Serra b , Stéphane Le Calvé a a Laboratoire des Matériaux, Surfaces et Procédés pour la Catalyse (LMSPC, UMR 7515 CNRS/UdS), Group of Atmospheric Physical Chemistry, 25 rue Becquerel, 67087 Strasbourg Cedex 02, France b Université de Strasbourg (UdS), Ecole de Chimie Polymères et Matériaux (ECPM), Laboratoire d’Ingénierie des Polymères pour les Hautes Technologies (LIPHT) – EAc(CNRS) 4379, Groupe d’Intensification et d’Intrapolation des Procédés Polymères (G2IP), F-67087 Strasbourg, France a r t i c l e i n f o Article history: Received 5 November 2012 Received in revised form 7 January 2013 Accepted 11 February 2013 Available online 18 February 2013 Keywords: Formaldehyde Real-time analysis Sensitivity Miniaturization a b s t r a c t Formaldehyde is a colorless gas emitted into the indoor environment by furniture and many other sources. In 2006, International Agency for Research on Cancer (IARC) classified formaldehyde as carcinogen to humans even at low concentrations. The World Health Organization (WHO) determined a guideline value of 82 ppb (parts per billion). Standard analysis based on sampling and then gas chromatography (GC) or high-performance liquid chromatography (HPLC) methods are off-line methods and are considered to be time-consuming and cumbersome, in addition to their large sizes, weights, high cost in terms of both equipment and consumables. This review reports the developments made over the last decade toward the realization of portable, high sensitive and real-time formaldehyde analyzers. © 2013 Elsevier B.V. All rights reserved. Contents 1. Introduction ...... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 551 2. Colorimetry and fluorescence-based formaldehyde analyzer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 552 2.1. Adsorption on doped surfaces and direct analysis ...... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 552 2.2. Uptake into an aqueous reactant solution and subsequent analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 555 3. Conclusion ...... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 556 Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 556 References .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 556 Biographies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 557 1. Introduction Formaldehyde (HCHO) is a colorless gas that is readily soluble in water but not in most organic solvents, except alcohol and ether [1]. The human body consists of hydrocarbons among its components, and it requires formaldehyde to metabolize biochemical substances [2]. Formaldehyde constitutes a part of our general outdoor environ- ment. It is released into the atmospheric air by means of automobile fumes, industrial facilities that burn fossil fuels, forest fires and the ∗ Corresponding author at: Laboratoire des Matériaux, Surfaces et Procédés pour la Catalyse (LMSPC, UMR 7515 CNRS/UdS), Group of Atmospheric Physical Chem- istry, 25 rue Becquerel, 67087 Strasbourg Cedex 02, France. Tel.: +33 682829081. E-mail address: aedallou@live.fr (A. Allouch). open burning of waste [3,4]. Because of its high water solubility, formaldehyde is contained in rain water, oceans and surface waters [1]. Formaldehyde is also highly present in human indoor environ- ment. Formaldehyde resins are used in the production of plywood and particle board [5]. Paper products treated with formaldehyde include paper bags, waxed paper, paper towels and disposable sanitary products [6,7] which are usually used in human work environment. Formaldehyde also finds its way into the workplace through other textile products [8,9]. It has been stated that the concentration of formaldehyde in the indoor areas is usually 2–10 times higher than the outdoor concentration, and it is in the range of several tens of ppb [6,10–13]. The major anthropogenic sources that influence human health are found in the indoor environment where people spend more than 80% of their time. OSHA (Occupational Safety and Health Administration) deter- mined that formaldehyde is genotoxic, showing properties of 0925-4005/$ – see front matter © 2013 Elsevier B.V. All rights reserved. http://dx.doi.org/10.1016/j.snb.2013.02.043