Sensitivity improved surface plasmon resonance biosensor for cancer biomarker detection based on plasmonic enhancement

Wing Cheung Law, Ken Tye Yong, Alexander Baev, Paras N. Prasad

Research output: Journal article publicationJournal articleAcademic researchpeer-review

210 Citations (Scopus)


In this study, we report the development of a nanoparticle-enhanced biosensor by integrating both the nanoparticles and immunoassay sensing technologies into a phase interrogation surface plasmon resonance (SPR) system for detecting antigen at a concentration as low as the femtomolar range. Our work has demonstrated that the plasmonic field extension generated from the gold film to gold nanorod (GNR) has led to a drastic sensitivity enhancement. Antibody-functionalized sensing film, together with antibody-conjugated GNRs, was readily served as a plasmonic coupling partner that can be used as a powerful ultrasensitive sandwich immunoassay for cancer-related disease detection. Experimentally, it was found that the bioconjugated GNR labels enhance the tumor necrosis factor alpha (TNF-α) antigen signal with more than 40-fold increase compared to the traditional SPR biosensing technique. The underlying principle was analyzed by simulating the near-field coupling between the sensing film and the GNR. The results have shown that GNRs were readily served as promising amplification labels in SPR sensing technology.
Original languageEnglish
Pages (from-to)4858-4864
Number of pages7
JournalACS Nano
Issue number6
Publication statusPublished - 28 Jun 2011
Externally publishedYes


  • biosensor
  • gold nanorod
  • surface plasmon resonance
  • TNF-α

ASJC Scopus subject areas

  • Materials Science(all)
  • Engineering(all)
  • Physics and Astronomy(all)

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