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PubMed · 17110096

Label-free immunosensor for prostate-specific antigen based on single-walled carbon nanotube array-modified microelectrodes.

Jun Okuno·Kenzo Maehashi·Kagan Kerman·Yuzuru Takamura·Kazuhiko Matsumoto·Eiichi Tamiya
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Abstract

We have fabricated a label-free electrochemical immunosensor using microelectrode arrays modified with single-walled carbon nanotubes (SWNTs). Label-free detection of a cancer marker, total prostate-specific antigen (T-PSA), was carried out using differential pulse voltammetry (DPV). The current signals, derived from the oxidation of tyrosine (Tyr), and tryptophan (Trp) residues, increased with the interaction between T-PSA on T-PSA-mAb covalently immobilized on SWNTs. The selectivity of our biosensor was challenged using bovine serum albumin (BSA) as the target protein. The detection limit for T-PSA was determined as 0.25 ng/mL. Since the cut-off limit of T-PSA between prostate hyperplasia and cancer is 4 ng/mL, the performance of our label-free electrochemical immunosensor seems promising for further clinical applications.

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Biosensing TechniquesImmunoassayMicroelectrodesNanotubes, CarbonProstate-Specific AntigenJournal ArticleResearch Support, Non-U.S. Gov't

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Jun Okuno, Kenzo Maehashi, Kagan Kerman, Yuzuru Takamura, Kazuhiko Matsumoto, Eiichi Tamiya. 2006-11-15. Label-free immunosensor for prostate-specific antigen based on single-walled carbon nanotube array-modified microelectrodes.. https://doi.org/10.1016/j.bios.2006.09.038

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