title: A supramolecular sensing platform for phosphate anions and an anthrax biomarker in a microfluidic device.
abstract: A supramolecular platform based on self-assembled monolayers (SAMs) has been implemented in a microfluidic device. The system has been applied for the sensing of two different analyte types: biologically relevant phosphate anions and aromatic carboxylic acids, which are important for anthrax detection. A Eu(III)-EDTA complex was bound to β-cyclodextrin monolayers via orthogonal supramolecular host-guest interactions. The self-assembly of the Eu(III)-EDTA conjugate and naphthalene β-diketone as an antenna resulted in the formation of a highly luminescent lanthanide complex on the microchannel surface. Detection of different phosphate anions and aromatic carboxylic acids was demonstrated by monitoring the decrease in red emission following displacement of the antenna by the analyte. Among these analytes, adenosine triphosphate (ATP) and pyrophosphate, as well as dipicolinic acid (DPA) which is a biomarker for anthrax, showed a strong response. Parallel fabrication of five sensing SAMs in a single multichannel chip was performed, as a first demonstration of phosphate and carboxylic acid screening in a multiplexed format that allows a general detection platform for both analyte systems in a single test run with μM and nM detection sensitivity for ATP and DPA, respectively.
authors.affiliation: Mesoscale Chemical Systems, MESA+ Institute for Nanotechnology, University of Twente, 7500 AE, Enschede, The Netherlands; E-Mails:  b.eker@utwente.nl  (B.E.);  s.schlautmann@utwente.nl  (S.S.).
authors.forename: Bilge
authors.initials: B
authors.lastname: Eker
authors.forename: Mahmut Deniz
authors.initials: MD
authors.lastname: Yilmaz
authors.forename: Stefan
authors.initials: S
authors.lastname: Schlautmann
authors.forename: Johannes G E
authors.initials: JG
authors.lastname: Gardeniers
authors.forename: Jurriaan
authors.initials: J
authors.lastname: Huskens
mesh_terms: D000255:Adenosine Triphosphate / Q000032:analysis; D000838:Anions / Q000737:chemistry*; D001408:Bacillus anthracis / Q000302:isolation & purification; D015415:Biomarkers / Q000032:analysis; D011756:Diphosphates / Q000032:analysis; D049449:Luminescence; D046208:Microchip Analytical Procedures; D046210:Microfluidic Analytical Techniques / Q000379:methods*; D010710:Phosphates / Q000737:chemistry*; D010848:Picolinic Acids / Q000032:analysis; D047392:beta-Cyclodextrins
chemical_list: D000838:Anions; D015415:Biomarkers; D011756:Diphosphates; D010710:Phosphates; D010848:Picolinic Acids; D047392:beta-Cyclodextrins; C107241:diphosphoric acid; D000255:Adenosine Triphosphate; C031215:betadex; C004860:dipicolinic acid