title: Detection of the early stage of recombinational DNA repair by silicon nanowire transistors.
abstract: A silicon nanowire-based biosensor has been designed and applied for label-free and ultrasensitive detection of the early stage of recombinational DNA repair by RecA protein. Silicon nanowires transistors were fabricated by atomic force microscopy nanolithography and integrated into a microfluidic environment. The sensor operates by measuring the changes in the resistance of the nanowire as the biomolecular reactions proceed. We show that the nanoelectronic sensor can detect and differentiate several steps in the binding of RecA to a single-stranded DNA filament taking place on the nanowire-aqueous interface. We report relative changes in the resistance of 3.5% which are related to the interaction of 250 RecA·single-stranded DNA complexes. Spectroscopy data confirm the presence of the protein-DNA complexes on the functionalized silicon surfaces.
authors.affiliation: Instituto de Microelectrónica de Madrid (IMM-CNM-CSIC), Isaac Newton 8, 28760 Tres Cantos, Madrid, Spain.
authors.forename: Marco
authors.initials: M
authors.lastname: Chiesa
authors.forename: Paula P
authors.initials: PP
authors.lastname: Cardenas
authors.forename: Francisco
authors.initials: F
authors.lastname: Otón
authors.forename: Javier
authors.initials: J
authors.lastname: Martinez
authors.forename: Marta
authors.initials: M
authors.lastname: Mas-Torrent
authors.forename: Fernando
authors.initials: F
authors.lastname: Garcia
authors.forename: Juan C
authors.initials: JC
authors.lastname: Alonso
authors.forename: Concepció
authors.initials: C
authors.lastname: Rovira
authors.forename: Ricardo
authors.initials: R
authors.lastname: Garcia
mesh_terms: D000818:Animals; D003217:Conductometry / Q000295:instrumentation*; D004260:DNA Repair / Q000502:physiology*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006801:Humans; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation*; D043942:Nanotubes / Q000737:chemistry* / Q000648:ultrastructure; D010316:Particle Size; D011938:Rec A Recombinases / Q000378:metabolism*; D011995:Recombination, Genetic / Q000502:physiology*; D012825:Silicon / Q000737:chemistry; D014173:Transistors, Electronic
chemical_list: D011938:Rec A Recombinases; D012825:Silicon