Release Time:2019-03-12  Hits:

Indexed by: Journal Article

Date of Publication: 2017-06-01

Journal: PLASMONICS

Included Journals: Scopus、SCIE

Volume: 12

Issue: 3

Page Number: 663-673

ISSN: 1557-1955

Key Words: Surface plasmon; Sensors; Optical sensing and sensors; Biological sensing and sensors

Abstract: In this paper, we report a novel wavelength interrogation-based surface plasmon resonance (SPR) system, in which a film of three Ag layers and three Au layers are alternately deposited on a Kretschmann configuration as sensing element. This multilayer film shows higher sensitivity for refractive index (RI) measurement by comparing with single Au layer structure, which is consistent with its theoretical calculation. A sensitivity range of 2056-5893 nm/RIU can be achieved, which is comparable to RI sensitivities of other wavelength-modulated SPR sensors. Compared with Ag film, this Ag/Au multilayer arrangement offers anti-oxidant protection. This SPR biosensor based on a cost-effective Ag/Au multilayer structure is applicable to the real-time detection of specific interactions and dissociation of low protein concentrations. To extend the application of this highly-sensitive metal film device, we integrated this concept on an optical fiber. The range of RI sensitivities with Ag/Au multilayer was 1847-3309 nm/RIU. This miniaturized Ag/Au multilayer-based fiber optic sensor has a broad application in chemical and biological sensing.