title: Aptamer-based Field-Effect Biosensor for Tenofovir Detection.
abstract: During medical treatment it is critical to maintain the circulatory concentration of drugs within their therapeutic range. A novel biosensor is presented in this work to address the lack of a reliable point-of-care drug monitoring system in the market. The biosensor incorporates high selectivity and sensitivity by integrating aptamers as the recognition element and field-effect transistors as the signal transducer. The drug tenofovir was used as a model small molecule. The biointerface of the sensor is a binary self-assembled monolayer of specific thiolated aptamer and 6-mercapto-1-hexanol (MCH), whose ratio was optimized by electrochemical impedance spectroscopy measurements to enhance the sensitivity towards the specific target. Surface plasmon resonance, performed under different buffer conditions, shows optimum specific and little non-specific binding in phosphate buffered saline. The dose-response behavior of the field-effect biosensor presents a linear range between 1 nM and 100 nM of tenofovir and a limit of detection of 1.2 nM. Two non-specific drugs and one non-specific aptamer, tested as stringent control candidates, caused negligible responses. The applications were successfully extended to the detection of the drug in human serum. As demonstrated by impedance measurements, the aptamer-based sensors can be used for real-time drug monitoring.
authors.affiliation: School of Engineering, École Polytechnique Fédérale de Lausanne (EPFL), STI-IEL-LSI2, Building INF, 3rd floor, 1015 Lausanne, Switzerland.
authors.forename: N
authors.initials: N
authors.lastname: Aliakbarinodehi
authors.affiliation: Department of Electronic and Electrical Engineering, University of Bath, Claverton Down, BA2 7AY Bath, United Kingdom.
authors.forename: P
authors.initials: P
authors.lastname: Jolly
authors.affiliation: Department of Electronic and Electrical Engineering, University of Bath, Claverton Down, BA2 7AY Bath, United Kingdom.
authors.forename: N
authors.initials: N
authors.lastname: Bhalla
authors.affiliation: Department of Electronic and Electrical Engineering, University of Bath, Claverton Down, BA2 7AY Bath, United Kingdom.
authors.forename: A
authors.initials: A
authors.lastname: Miodek
authors.affiliation: School of Engineering, École Polytechnique Fédérale de Lausanne (EPFL), STI-IEL-LSI2, Building INF, 3rd floor, 1015 Lausanne, Switzerland.
authors.forename: G
authors.initials: G
authors.lastname: De Micheli
authors.affiliation: Department of Electronic and Electrical Engineering, University of Bath, Claverton Down, BA2 7AY Bath, United Kingdom.
authors.forename: P
authors.initials: P
authors.lastname: Estrela
authors.affiliation: School of Engineering, École Polytechnique Fédérale de Lausanne (EPFL), STI-IEL-LSI2, Building INF, 3rd floor, 1015 Lausanne, Switzerland.
authors.forename: S
authors.initials: S
authors.lastname: Carrara
mesh_terms: D052157:Aptamers, Nucleotide / Q000737:chemistry; D015374:Biosensing Techniques; D058266:Dielectric Spectroscopy; D016903:Drug Monitoring; D055664:Electrochemical Techniques; D000441:Hexanols / Q000737:chemistry; D006801:Humans; D057230:Limit of Detection; D013438:Sulfhydryl Compounds / Q000737:chemistry; D020349:Surface Plasmon Resonance; D000068698:Tenofovir / Q000737:chemistry / Q000302:isolation & purification* / Q000627:therapeutic use
chemical_list: C503488:6-mercapto-1-hexanol; D052157:Aptamers, Nucleotide; D000441:Hexanols; D013438:Sulfhydryl Compounds; D000068698:Tenofovir