Attomolar label-free detection of DNA hybridization with electrolyte-gated Graphene field-effect transistors

• Autor(a) principal: Campos, Rui
• Data de Publicação: 2019
• Outros Autores: Borme, Jérôme, Guerreiro, Joana Rafaela, Machado, George, Cerqueira, M. F., Petrovykh, Dmitri Y., Alpuim, P.
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/1822/69035
• topic: Biosensor; DNA; EGFET (electrolyte-gated field-effect transistor); Graphite; Models, Molecular; Molecular Conformation; Nucleic Acid Hybridization; Polymorphism, Single Nucleotide; Surface Properties; Limit of Detection; Transistors, Electronic; Graphene; Planar technology; Receded gate transistor; Surface functionalization; Ciências Médicas::Biotecnologia Médica; Science & Technology; Saúde de qualidade

In this work, we develop a field-effect transistor with a two-dimensional channel made of a single graphene layer to achieve label-free detection of DNA hybridization down to attomolar concentration, while being able to discriminate a single nucleotide polymorphism (SNP). The SNP-level target specificity is achieved by immobilization of probe DNA on the graphene surface through a pyrene-derivative heterobifunctional linker. Biorecognition events result in a positive gate voltage shift of the graphene charge neutrality point. The graphene transistor biosensor displays a sensitivity of 24 mV/dec with a detection limit of 25 aM: the lowest target DNA concentration for which the sensor can discriminate between a perfect-match target sequence and SNP-containing one.