Comparative study of label-free electrochemical immunoassay on various gold nanostructures
Electrochemical methods such as amperometry and impedance spectroscopy provide the feasibility of label-free immunoassay. However, the performance of electrochemical interfaces varies with the shape of gold nanostructures. In the present work three types of gold nanostructures including pyramid, sph...
| Main Authors: | , , , |
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| Other Authors: | |
| Format: | Journal Article |
| Language: | English |
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2014
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| Online Access: | https://hdl.handle.net/10356/98390 http://hdl.handle.net/10220/18436 |
| _version_ | 1826112776379039744 |
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| author | Rafique, S. Gao, C. Li, C. M. Bhatti, A. S. |
| author2 | School of Chemical and Biomedical Engineering |
| author_facet | School of Chemical and Biomedical Engineering Rafique, S. Gao, C. Li, C. M. Bhatti, A. S. |
| author_sort | Rafique, S. |
| collection | NTU |
| description | Electrochemical methods such as amperometry and impedance spectroscopy provide the feasibility of label-free immunoassay. However, the performance of electrochemical interfaces varies with the shape of gold nanostructures. In the present work three types of gold nanostructures including pyramid, spherical, and rod-like nanostructures were electrochemically synthesized on the gold electrode and were further transformed into immunosensor by covalent binding of antibodies. As a model protein, a cancer biomarker, Carcinoembryonic Antigen (CEA) was detected using amperometric and impedimetric techniques on three nanostructured electrodes, which enabled to evaluate and compare the immunoassay's performance. It was found that all three immunosensors showed improved linear electrochemical response to the concentration of CEA compared to bare Au electrode. Among all the spherical gold nanostructure based immunosensors displayed superior performance. Under optimal condition, the immunosensors exhibited a limit of detection of 4.1 pg ml−1 over a concentration range of five orders of magnitude. This paper emphasizes that fine control over the geometry of nanostructures is essentially important for high-performance electrochemical immunoassay. |
| first_indexed | 2024-10-01T03:12:20Z |
| format | Journal Article |
| id | ntu-10356/98390 |
| institution | Nanyang Technological University |
| language | English |
| last_indexed | 2024-10-01T03:12:20Z |
| publishDate | 2014 |
| record_format | dspace |
| spelling | ntu-10356/983902023-12-29T06:46:17Z Comparative study of label-free electrochemical immunoassay on various gold nanostructures Rafique, S. Gao, C. Li, C. M. Bhatti, A. S. School of Chemical and Biomedical Engineering DRNTU::Engineering::Chemical engineering Electrochemical methods such as amperometry and impedance spectroscopy provide the feasibility of label-free immunoassay. However, the performance of electrochemical interfaces varies with the shape of gold nanostructures. In the present work three types of gold nanostructures including pyramid, spherical, and rod-like nanostructures were electrochemically synthesized on the gold electrode and were further transformed into immunosensor by covalent binding of antibodies. As a model protein, a cancer biomarker, Carcinoembryonic Antigen (CEA) was detected using amperometric and impedimetric techniques on three nanostructured electrodes, which enabled to evaluate and compare the immunoassay's performance. It was found that all three immunosensors showed improved linear electrochemical response to the concentration of CEA compared to bare Au electrode. Among all the spherical gold nanostructure based immunosensors displayed superior performance. Under optimal condition, the immunosensors exhibited a limit of detection of 4.1 pg ml−1 over a concentration range of five orders of magnitude. This paper emphasizes that fine control over the geometry of nanostructures is essentially important for high-performance electrochemical immunoassay. Published version 2014-01-10T03:52:18Z 2019-12-06T19:54:44Z 2014-01-10T03:52:18Z 2019-12-06T19:54:44Z 2013 2013 Journal Article Rafique, S., Gao, C., Li, C. M., & Bhatti, A. S. (2013). Comparative study of label-free electrochemical immunoassay on various gold nanostructures. Journal of applied physics, 114(16), 164703-. 0021-8979 https://hdl.handle.net/10356/98390 http://hdl.handle.net/10220/18436 10.1063/1.4827381 en Journal of applied physics © 2013 AIP Publishing LLC. This paper was published in Journal of Applied Physics and is made available as an electronic reprint (preprint) with permission of AIP Publishing LLC. The paper can be found at the following official DOI: [http://dx.doi.org/10.1063/1.4827381]. One print or electronic copy may be made for personal use only. Systematic or multiple reproduction, distribution to multiple locations via electronic or other means, duplication of any material in this paper for a fee or for commercial purposes, or modification of the content of the paper is prohibited and is subject to penalties under law. application/pdf |
| spellingShingle | DRNTU::Engineering::Chemical engineering Rafique, S. Gao, C. Li, C. M. Bhatti, A. S. Comparative study of label-free electrochemical immunoassay on various gold nanostructures |
| title | Comparative study of label-free electrochemical immunoassay on various gold nanostructures |
| title_full | Comparative study of label-free electrochemical immunoassay on various gold nanostructures |
| title_fullStr | Comparative study of label-free electrochemical immunoassay on various gold nanostructures |
| title_full_unstemmed | Comparative study of label-free electrochemical immunoassay on various gold nanostructures |
| title_short | Comparative study of label-free electrochemical immunoassay on various gold nanostructures |
| title_sort | comparative study of label free electrochemical immunoassay on various gold nanostructures |
| topic | DRNTU::Engineering::Chemical engineering |
| url | https://hdl.handle.net/10356/98390 http://hdl.handle.net/10220/18436 |
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