title: Impact of DNA sequence and oligonucleotide length on a polythiophene-based fluorescent DNA biosensor.
abstract: DNA hybridization is a universal and specific mechanism for the recognition of biological targets. Some cationic polythiophene transducers sensitive to DNA structure have been previously utilized to detect such biomolecules. Further characterization of these systems indicates that both DNA sequence composition and length modulate the biosensor performance. It appears that different repeated sequence patterns cause different conformational changes of the polythiophene, from a more relaxed form to an extremely rigid one. A length difference between the DNA oligonucleotide probe and target has a detrimental effect on the fluorescent signal, but it can be attenuated by changing the sequence composition of the protruding target sequence. This demonstrates that the nature of DNA can be critical for hybridization-based detection systems.
authors.affiliation: Centre de recherche du CHU de Québec, Département de Microbiologie-infectiologie et immunologie, Faculté de médecine, Université Laval, 2705 Laurier Blvd., Quebec City, QC, G1V 4G2, Canada.
authors.forename: Isabelle
authors.initials: I
authors.lastname: Charlebois
authors.forename: Catherine
authors.initials: C
authors.lastname: Gravel
authors.forename: Naoual
authors.initials: N
authors.lastname: Arrad
authors.forename: Maurice
authors.initials: M
authors.lastname: Boissinot
authors.forename: Michel G
authors.initials: MG
authors.lastname: Bergeron
authors.forename: Mario
authors.initials: M
authors.lastname: Leclerc
mesh_terms: D001483:Base Sequence; D015374:Biosensing Techniques / Q000379:methods*; D004247:DNA / Q000032:analysis*; D015342:DNA Probes / Q000378:metabolism; D009841:Oligonucleotides / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry*; D013050:Spectrometry, Fluorescence; D013056:Spectrophotometry, Ultraviolet; D013876:Thiophenes / Q000737:chemistry*
chemical_list: D015342:DNA Probes; D009841:Oligonucleotides; D011108:Polymers; D013876:Thiophenes; C066730:polythiophene; D004247:DNA