title: Part per trillion label-free electronic bioanalytical detection.
abstract: A Functional Bio-Interlayer Organic Field-Effect Transistor (FBI-OFET) sensor, embedding a streptavidin protein capturing layer, capable of performing label-free selective electronic detection of biotin at 3 part per trillion (mass fraction) or 15 pM, is proposed here. The response shows a logarithmic dependence spanning over 5 orders of magnitude of analyte concentration. The optimization of the FBI analytical performances is achieved by depositing the capturing layer through a controllable Layer-by-Layer (LbL) assembly, while an easy processable spin-coating deposition is proposed for potential low-cost production of equally highly performing sensors. Furthermore, a Langmuirian adsorption based model allows rationalizing the analyte binding process to the capturing layer. The FBI-OFET device is shown to operate also with an antibody interlayer as well as with an ad hoc designed microfluidic system. These occurrences, along with the proven extremely high sensitivity and selectivity, open to FBI-OFETs consideration as disposable electronic strip-tests for assays in biological fluids requiring very low detection limits.
authors: Dipartimento di Chimica, Università degli Studi di Bari A. Moro-Via Orabona, 4 70126 Bari, Italy. maria.magliulo@uniba.it
authors: Maria
authors: M
authors: Magliulo
authors: Antonia
authors: A
authors: Mallardi
authors: Roberto
authors: R
authors: Gristina
authors: Francesca
authors: F
authors: Ridi
authors: Luigia
authors: L
authors: Sabbatini
authors: Nicola
authors: N
authors: Cioffi
authors: Gerardo
authors: G
authors: Palazzo
authors: Luisa
authors: L
authors: Torsi
mesh_terms: D000327:Adsorption; D000906:Antibodies / Q000737:chemistry; D001710:Biotin / Q000032:analysis*; D055664:Electrochemical Techniques / Q000295:instrumentation* / Q000379:methods; D005456:Fluorescent Dyes; D055767:Immobilized Proteins / Q000737:chemistry; D007700:Kinetics; D046210:Microfluidic Analytical Techniques; D011934:Reagent Strips; D012680:Sensitivity and Specificity; D019809:Streptavidin / Q000737:chemistry*; D014173:Transistors, Electronic
chemical_list: D000906:Antibodies; D005456:Fluorescent Dyes; D055767:Immobilized Proteins; D011934:Reagent Strips; D001710:Biotin; D019809:Streptavidin