Jump to main content
Jump to site search

Issue 40, 2019
Previous Article Next Article

Antenna array-enhanced attenuated total reflection IR analysis in an aqueous solution

Author affiliations

Abstract

Attenuated total reflection surface-enhanced infrared absorption spectroscopy (ATR-SEIRAS) is a powerful technique that provides structural and functional information during dynamic reactions in aqueous solutions. One existing limitation is the sensitivity to extract the signals of trace-level analytes from the background water in situ and in real time. Here, we proposed a novel ATR-SEIRAS platform that integrated a large-scale triangle gold antenna array onto a conventional ATR-IR platform to increase the sensitivity of this analytical technique. A square centimeter level well-ordered gold antenna array was fabricated onto an Si prism via nanosphere lithography. The size-dependent antenna array resonance had weak correlation with the incident polarization and antenna orientation, allowing antenna array-enhanced IR detection without the requirement of a microscope. In addition, the antenna resonance shift that occurred due to analyte adsorption-induced refractive index variation could be minimized benefiting from the high refractive index of Si (3.4). As a demonstration, we dynamically monitored the adsorption of the trace levels of proteins on top of the antenna array with a real signal enhancement factor larger than 300. Our platform opens an avenue to apply antenna array-enhanced IR spectroscopy in an aqueous environment measured via commercial IR instruments, which is extremely promising for the interfacial applications that require signal enhancement.

Graphical abstract: Antenna array-enhanced attenuated total reflection IR analysis in an aqueous solution

Back to tab navigation

Supplementary files

Publication details

The article was received on 12 May 2019, accepted on 22 Sep 2019 and first published on 23 Sep 2019


Article type: Communication
DOI: 10.1039/C9NR04032C
Nanoscale, 2019,11, 18543-18549

  •   Request permissions

    Antenna array-enhanced attenuated total reflection IR analysis in an aqueous solution

    J. Li, Z. Yan, J. Li, Z. Wang, W. Morrison and X. Xia, Nanoscale, 2019, 11, 18543
    DOI: 10.1039/C9NR04032C

Search articles by author

Spotlight

Advertisements