Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
7234157 | Biosensors and Bioelectronics | 2013 | 5 Pages |
Abstract
Biochemical and biomedical applications of graphene are critically dependent on the interaction between biomolecules and the nanomaterial. In this work, we developed a graphene-based signal-amplification nanoprobe by combining anti-immunoglobulin G (anti-IgG) and horseradish peroxidase (HRP) with graphene oxide (GO). The structure and function of HRP in the nano-interface of GO were firstly investigated, which demonstrated that the enzyme retained 78% of its native activity and 77% of its native α-helix content. HRP and anti-IgG were then co-adsorbed onto GO to form bifunctional nanoprobes. The nanoprobes provide both improved binding ability and signal-amplification ability. Comparing with conventional bioconjugates such as enzyme-linked antibody, co-adsorption could avoid chemical conjugation between biomolecules, keeping their bioactivity well. As an example for their application, the nanoprobes were used to obtain amplified signals in a sandwich-type immunoassay for cancer marker, instead of conventional colorimetric conjugates. This approach provided a detection limit of 10 pg/mL alpha-fetoprotein (AFP), which was much more sensitive than conventional enzyme-linked immunosorbent assay (ELISA) methods. The easily fabricated GO-based nanoprobes have the potential to become universal probes for molecular diagnostics.
Related Topics
Physical Sciences and Engineering
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Authors
Hui Xu, Dongfang Wang, Shijiang He, Jiang Li, Bianying Feng, Peijun Ma, Pingping Xu, Shanmin Gao, Shengxiao Zhang, Quanwen Liu, Jianxin Lu, Shiping Song, Chunhai Fan,