Coupling Single-Drop Microextraction with SERS: A Demonstration Using p-MBA on Gold Nanohole Array Substrate

Author(s)

Santos, Elias B. ^[1] ; Valsecchi, Chiara ^[2] ; Goncalves, Jaderson L. S. ^[2] ; Avila, Luis F. ^[3] ; Menezes, Jacson W. ^[2]

Affiliation

^[1] Univ Fed Sao Paulo, LQANano, BR-12231280 Sao Jose Dos Campos, SP - Brazil

^[2] Fed Univ Pampa, Engn Dept, BR-97546550 Alegrete, RS - Brazil

^[3] Univ Estadual Campinas, Sch Technol, Appl Opt Lab, BR-13484350 Limeira, SP - Brazil

• Document type: Journal article
• Source: SENSORS; v. 19, n. 20 OCT 2 2019.
• Web of Science Citations: 0

Abstract

Single-drop microextraction (SDME) was coupled with surface-enhanced Raman scattering (SERS) to provide sample extraction and pre-concentration for detection of analyte at low concentrations. A gold nanohole array substrate (AuNHAS), fabricated by interference lithography, was used as SERS substrate and para-mercaptobenzoic acid (p-MBA) was tested as a probe molecule, in the concentration range 10(-8)-10(-4) mol L-1. With this approach, a limit of 10(-7) mol L-1 was clearly detected. To improve the detection to lower p-MBA concentration, as 10(-8) mol L-1, the SDME technique was applied. The p-MBA Raman signature was detected in two performed extractions and its new concentration was determined to be similar to 4.6 x 10(-5) mol L-1. This work showed that coupling SDME with SERS allowed a rapid (5 min) and efficient pre-concentration (from 10 8 mol L-1 to 10(-5) mol L-1), detection, and quantification of the analyte of interest, proving to be an interesting analytical tool for SERS applications. (AU)

• FAPESP's process: 15/16573-5 - Plasmonic nanoparticles of silver, gold, and copper: synthetic methods, preparation of reproducible plasmonic and SERS sensors for environmental applications
• Grantee: Elias de Barros Santos
• Support Opportunities: Regular Research Grants