title: Plasmonic liquid marbles: a miniature substrate-less SERS platform for quantitative and multiplex ultratrace molecular detection.
abstract: Inspired by aphids, liquid marbles have been studied extensively and have found application as isolated microreactors, as micropumps, and in sensing. However, current liquid-marble-based sensing methodologies are limited to qualitative colorimetry-based detection. Herein we describe the fabrication of a plasmonic liquid marble as a substrate-less analytical platform which, when coupled with ultrasensitive SERS, enables simultaneous multiplex quantification and the identification of ultratrace analytes across separate phases. Our plasmonic liquid marble demonstrates excellent mechanical stability and is suitable for the quantitative examination of ultratrace analytes, with detection limits as low as 0.3 fmol, which corresponds to an analytical enhancement factor of 5×10(8). The results of our simultaneous detection scheme based on plasmonic liquid marbles and an aqueous-solid-organic interface quantitatively tally with those found for the individual detection of methylene blue and coumarin.
authors.affiliation: Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, 50 Nanyang Ave, Singapore 637371 (Singapore).
authors.forename: Hiang Kwee
authors.initials: HK
authors.lastname: Lee
authors.forename: Yih Hong
authors.initials: YH
authors.lastname: Lee
authors.forename: In Yee
authors.initials: IY
authors.lastname: Phang
authors.forename: Jiaqi
authors.initials: J
authors.lastname: Wei
authors.forename: Yue-E
authors.initials: YE
authors.lastname: Miao
authors.forename: Tianxi
authors.initials: T
authors.lastname: Liu
authors.forename: Xing Yi
authors.initials: XY
authors.lastname: Ling
mesh_terms: D003374:Coumarins / Q000032:analysis; D057230:Limit of Detection; D008751:Methylene Blue / Q000032:analysis
chemical_list: D003374:Coumarins; C030123:coumarin; D008751:Methylene Blue
keywords: liquid marbles; multiplex detection; sensors; surface-enhanced Raman spectroscopy; ultratrace detection