Direct molecular detection of nucleic acids by fluorescence signal amplification.
An integrated PCR-free DNA sensor, which combines a sequence-specific receptor, an optical polymeric transducer, and an intrinsic fluorescence amplification mechanism, is reported. This sensor is based on the different conformations adopted by a cationic polythiophene when electrostatically bound to ss-DNA or ds-DNA, and on the efficient and fast energy transfer between the resulting fluorescent polythiophene/ds-DNA complex and neighboring fluorophores attached to ss-DNA probes. This molecular system allows the detection of only five molecules in 3 mL of an aqueous solution, or 3 zM, in 5 min. Moreover, this work demonstrates, for the first time, the direct detection of single nucleotide polymorphisms (SNPs) from clinical samples in only a few minutes, without the need for nucleic acid amplification.
Ho
Hoang A
HA
Department of Chemistry, the Research Center in Infectiology and the Laboratory of Cell and Developmental Genetics, Université Laval, Québec City, Qc, Canada G1K 7P4.
Doré
Kim
K
Boissinot
Maurice
M
Bergeron
Michel G
MG
Tanguay
Robert M
RM
Boudreau
Denis
D
Leclerc
Mario
M
D015374:Biosensing Techniques; D004247:DNA / Q000737:chemistry; D004277:DNA, Single-Stranded / Q000737:chemistry; D009696:Nucleic Acids / Q000032:analysis / Q000737:chemistry*; D012680:Sensitivity and Specificity; D013050:Spectrometry, Fluorescence / Q000379:methods
D004277:DNA, Single-Stranded; D009696:Nucleic Acids; D004247:DNA