Dataset Information

Chemiplasmonics for high-throughput biosensors.

ABSTRACT:

Background

The sensitivity of ELISA for biomarker detection can be significantly increased by integrating fluorescence with plasmonics. In surface-plasmon-coupled emission, the fluorophore emission is generally enhanced through the so-called physical mechanism due to an increase in the local electric field. Despite its fairly high enhancement factors, the use of surface-plasmon-coupled emission for high-throughput and point-of-care applications is still hampered due to the need for expensive focusing optics and spectrometers.

Methods

Here, we describe a new chemiplasmonic-sensing paradigm for enhanced emission through the molecular interactions between aromatic dyes and C₆₀ films on Ag substrates.

Results

A 20-fold enhancement in the emission from rhodamine B-labeled biomolecules can be readily elicited without quenching its red color emission. As a proof of concept, we demonstrate two model bioassays using: 1) the RhB-streptavidin and biotin complexes in which the dye was excited using an inexpensive laser pointer and the ensuing enhanced emission was recorded by a smartphone camera without the need for focusing optics and 2) high-throughput 96-well plate assay for a model antigen (rabbit immunoglobulin) that showed detection sensitivity as low as 6.6 pM.

Conclusion

Our results show clear evidence that chemiplasmonic sensors can be extended to detect biomarkers in a point-of-care setting through a smartphone in simple normal incidence geometry without the need for focusing optics. Furthermore, chemiplasmonic sensors also facilitate high-throughput screening of biomarkers in the conventional 96-well plate format with 10-20 times higher sensitivity.

SUBMITTER: Raghavendra AJ

PROVIDER: S-EPMC6267718 | biostudies-literature | 2018

REPOSITORIES: biostudies-literature

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Publications

Chemiplasmonics for high-throughput biosensors.

Raghavendra Achyut J AJ Zhu Jingyi J Gregory Wren W Case Fengjiao F Mulpur Pradyumna P Khan Shahzad S Srivastava Anurag A Podila Ramakrishna R

International journal of nanomedicine 20181127

<h4>Background</h4>The sensitivity of ELISA for biomarker detection can be significantly increased by integrating fluorescence with plasmonics. In surface-plasmon-coupled emission, the fluorophore emission is generally enhanced through the so-called physical mechanism due to an increase in the local electric field. Despite its fairly high enhancement factors, the use of surface-plasmon-coupled emission for high-throughput and point-of-care applications is still hampered due to the need for expen ...[more]

PMID: 30568445

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Dataset Information

Chemiplasmonics for high-throughput biosensors.

Background

Methods

Results

Conclusion

Publications

Chemiplasmonics for high-throughput biosensors.

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