TY - JOUR
T1 - An aptameric graphene nanosensor for label-free detection of small-molecule biomarkers
AU - Wang, Cheng
AU - Kim, Jinho
AU - Zhu, Yibo
AU - Yang, Jaeyoung
AU - Lee, Gwan Hyoung
AU - Lee, Sunwoo
AU - Yu, Jaeeun
AU - Pei, Renjun
AU - Liu, Guohua
AU - Nuckolls, Colin
AU - Hone, James
AU - Lin, Qiao
N1 - Publisher Copyright:
© 2015 Elsevier B.V.
PY - 2015/9/5
Y1 - 2015/9/5
N2 - This paper presents an aptameric graphene nanosensor for detection of small-molecule biomarkers. To address difficulties in direct detection of small molecules associated with their low molecular weight and electrical charge, we incorporate an aptamer-based competitive affinity assay in a graphene field effect transistor (FET), and demonstrate the utility of the nanosensor with dehydroepiandrosterone sulfate (DHEA-S), a small-molecule steroid hormone, as the target analyte. In the competitive affinity assay, DHEA-S specifically binds to aptamer molecules pre-hybridized to their complementary DNA anchor molecules immobilized on the graphene surface. This results in the competitive release of the strongly charged aptamer from the DNA anchor and hence a change in electrical properties of the graphene, which can be measured to achieve the detection of DHEA-S. We present experimental data on the label-free, specific and quantitative detection of DHEA-S at clinically appropriate concentrations with an estimated detection limit of 44.7. nM, and analyze the trend observed in the experiments using molecular binding kinetics theory. These results demonstrate the potential of our nanosensor in the detection of DHEA-S and other small molecules in biomedical applications.
AB - This paper presents an aptameric graphene nanosensor for detection of small-molecule biomarkers. To address difficulties in direct detection of small molecules associated with their low molecular weight and electrical charge, we incorporate an aptamer-based competitive affinity assay in a graphene field effect transistor (FET), and demonstrate the utility of the nanosensor with dehydroepiandrosterone sulfate (DHEA-S), a small-molecule steroid hormone, as the target analyte. In the competitive affinity assay, DHEA-S specifically binds to aptamer molecules pre-hybridized to their complementary DNA anchor molecules immobilized on the graphene surface. This results in the competitive release of the strongly charged aptamer from the DNA anchor and hence a change in electrical properties of the graphene, which can be measured to achieve the detection of DHEA-S. We present experimental data on the label-free, specific and quantitative detection of DHEA-S at clinically appropriate concentrations with an estimated detection limit of 44.7. nM, and analyze the trend observed in the experiments using molecular binding kinetics theory. These results demonstrate the potential of our nanosensor in the detection of DHEA-S and other small molecules in biomedical applications.
KW - Aptamer
KW - Competitive assay
KW - Dehydroepiandrosterone sulfate (DHEA-S)
KW - Graphene
KW - Nanobiosensor
KW - Small molecule
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U2 - 10.1016/j.bios.2015.04.025
DO - 10.1016/j.bios.2015.04.025
M3 - Article
C2 - 25912678
AN - SCOPUS:84928226249
SN - 0956-5663
VL - 71
SP - 222
EP - 229
JO - Biosensors and Bioelectronics
JF - Biosensors and Bioelectronics
ER -