title: An integrated superhydrophobic-plasmonic biosensor for mid-infrared protein detection at the femtomole level.
abstract: In this work we present an integrated biosensor that enables FTIR (Fourier Transform-Infrared) detection of analytes contained in diluted solutions. The fabricated nanosensor allows for the detection of proteins through the identification of the fine structure of their amide I and II bands, up to the nanomolar concentration range. We exploited two distinct effects to enhance the sensitivity: (i) the concentration effect due to the presence of the superhydrophobic surface that conveys molecules dispersed in solution directly inside the focus of a FTIR spectromicroscope; (ii) the plasmonic resonance of the nanoantenna array that provides electromagnetic field enhancement in the amide I and II spectral region (1500-1700 cm(-1)). We demonstrate the detection of ferritin in the nanomolar concentration range, a blood protein that is usually available in small amounts in typical blood samples.
authors.affiliation: CNR-Istituto di Fotonica e Nanotecnologie, Via Cineto Romano 42, 00146 Rome, Italy.
authors.forename: Adele
authors.initials: A
authors.lastname: De Ninno
authors.forename: Gabriele
authors.initials: G
authors.lastname: Ciasca
authors.forename: Annamaria
authors.initials: A
authors.lastname: Gerardino
authors.forename: Eugenio
authors.initials: E
authors.lastname: Calandrini
authors.forename: Massimiliano
authors.initials: M
authors.lastname: Papi
authors.forename: Marco
authors.initials: M
authors.lastname: De Spirito
authors.forename: Alessandro
authors.initials: A
authors.lastname: Nucara
authors.forename: Michele
authors.initials: M
authors.lastname: Ortolani
authors.forename: Luca
authors.initials: L
authors.lastname: Businaro
authors.forename: Leonetta
authors.initials: L
authors.lastname: Baldassarre
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation / Q000379:methods*; D057927:Hydrophobic and Hydrophilic Interactions; D049329:Nanostructures / Q000737:chemistry; D040081:Protein Array Analysis; D011506:Proteins / Q000032:analysis*; D017550:Spectroscopy, Fourier Transform Infrared
chemical_list: D011506:Proteins