On-chip FRET Graphene Oxide Aptasensor: Quantitative Evaluation of Enhanced Sensitivity by Aptamer with a Double-stranded DNA Spacer.
We propose a molecular design for a biomolecular probe to realize an on-chip graphene oxide (GO) aptasensor with enhanced sensitivity. Here, GO works as an excellent acceptor for fluorescence resonance energy transfer. We inserted a rigid double-stranded DNA as a spacer between the GO surface and the aptamer sequence to extend the distance between a fluorescence dye and the GO surface during molecular recognition. We examined the dependence of the sensitivity on the length of the spacer quantitatively by using a 2×2 linear-array aptasensor. We used the modified aptamer with 10 and 30 base pair (bp) double-stranded DNA spacers. The signal with a 30bp-spacer was about twice as strong that with a 10bp-spacer as regards both thrombin and prostate specific antigen detections. The improvement in the sensitivity was supported by a model calculation that estimated the effect of spacer length on fluorescence recovery efficiency.
NTT Basic Research Laboratories, NTT Corp.
Yuko
Y
Ueno
Kazuaki
K
Furukawa
Andrew
A
Tin
Hiroki
H
Hibino
D052157:Aptamers, Nucleotide / Q000235:genetics*; D001483:Base Sequence; D015374:Biosensing Techniques / Q000379:methods*; D004247:DNA / Q000737:chemistry* / Q000235:genetics; D015342:DNA Probes / Q000737:chemistry / Q000235:genetics; D031541:Fluorescence Resonance Energy Transfer; D006108:Graphite / Q000737:chemistry*; D006801:Humans; D057230:Limit of Detection; D046208:Microchip Analytical Procedures; D010087:Oxides / Q000737:chemistry*; D017430:Prostate-Specific Antigen / Q000032:analysis; D013499:Surface Properties; D013917:Thrombin / Q000032:analysis
D052157:Aptamers, Nucleotide; D015342:DNA Probes; D010087:Oxides; D006108:Graphite; D004247:DNA; D013917:Thrombin; D017430:Prostate-Specific Antigen