title: Potentiometric analytical microsystem based on the integration of a gas-diffusion step for on-line ammonium determination in water recycling processes in manned space missions.
abstract: The design, construction and evaluation of a versatile cyclic olefin copolymer (COC)-based continuous flow potentiometric microanalyzer to monitor the presence of ammonium ion in recycling water processes for future manned space missions is presented. The microsystem integrates microfluidics, a gas-diffusion module and a detection system in a single substrate. The gas-diffusion module was integrated by a hydrophobic polyvinylidene fluoride (PVDF) membrane. The potentiometric detection system is based on an all-solid state ammonium selective electrode and a screen-printed Ag/AgCl reference electrode. The analytical features provided by the analytical microsystem after the optimization process were a linear range from 0.15 to 500 mg L(-1) and a detection limit of 0.07 ± 0.01 mg L(-1). Nevertheless, the operational features can be easily adapted to other applications through the modification of the hydrodynamic variables of the microfluidic platform.
authors.affiliation: Group of Sensors and Biosensors, Department of Chemistry, Autonomous University of Barcelona, Edifici Cn, 08193 Bellaterra, Spain.
authors.forename: Antonio
authors.initials: A
authors.lastname: Calvo-López
authors.affiliation: Group of Sensors and Biosensors, Department of Chemistry, Autonomous University of Barcelona, Edifici Cn, 08193 Bellaterra, Spain.
authors.forename: Oriol
authors.initials: O
authors.lastname: Ymbern
authors.affiliation: Group of Sensors and Biosensors, Department of Chemistry, Autonomous University of Barcelona, Edifici Cn, 08193 Bellaterra, Spain.
authors.forename: Mar
authors.initials: M
authors.lastname: Puyol
authors.affiliation: NTE-SENER, Sabaters 1, 08290 Cerdanyola del Vallès, Spain.
authors.forename: Joan Manel
authors.initials: JM
authors.lastname: Casalta
authors.affiliation: Group of Sensors and Biosensors, Department of Chemistry, Autonomous University of Barcelona, Edifici Cn, 08193 Bellaterra, Spain. Electronic address: Julian.Alonso@uab.es.
authors.forename: Julián
authors.initials: J
authors.lastname: Alonso-Chamarro
mesh_terms: D064751:Ammonium Compounds / Q000032:analysis*; D003516:Cycloparaffins / Q000737:chemistry; D004058:Diffusion; D004566:Electrodes; D004867:Equipment Design; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation*; D011145:Polyvinyls / Q000737:chemistry; D011199:Potentiometry / Q000295:instrumentation*; D013026:Space Flight; D014867:Water / Q000032:analysis*; D005465:Fluorocarbon Polymers
chemical_list: D064751:Ammonium Compounds; D003516:Cycloparaffins; D011145:Polyvinyls; D014867:Water; C024865:polyvinylidene fluoride; D005465:Fluorocarbon Polymers
keywords: Ammonium ion; Gas-diffusion; Lab on a chip; Miniaturization; Polymer technology; Potentiometric detection