resumo
Research on paper substrates prepared by inkjet deposition of metal nanoparticles for sensing applications has become a hot topic in recent years; however, the design of such substrates based on the deposition of alloy nanoparticles remains less explored. Herein, we report for the first time the inkjet printing of dendrimer-stabilized colloidal metal nanoalloys for the preparation of paper substrates for surface enhanced Raman scattering (SERS) spectroscopy. To this end, nanoassemblies containing variable molar ratios of Au:Ag were prepared in the presence of poly(amidoamine) dendrimer (PAMAM), resulting in plasmonic properties that depend on the chemical composition of the final materials. The dendrimerstabilized Au:Ag:PAMAM colloids exhibit high colloidal stability, making them suitable for the preparation of inks for long-term use in inkjet printing of paper substrates. Moreover, the pre-treatment of paper with a polystyrene (PS) aqueous emulsion resulted in hydrophobic substrates with improved SERS sensitivity, as illustrated in the analytical detection of tetramethylthiuram disulfide (thiram pesticide) dissolved in aqueous solutions. We suggest that the interactions established between the two polymers (PAMAM and PS) in an interface region over the cellulosic fibres, resulted in more exposed metallic surfaces for the adsorption of the analyte molecules. The resulting hydrophobic substrates show longterm plasmonic stability with high SERS signal retention for at least ninety days. (c) 2021 Elsevier Inc. All rights reserved.
palavras-chave
POLY(AMIDOAMINE) DENDRIMERS; PAMAM DENDRIMERS; SERS SENSORS; SILVER; CHEMISTRY; SPECTROSCOPY; FABRICATION; PESTICIDES; INTERFACES; DESIGN
categoria
Chemistry
autores
Fernandes, T; Martins, NCT; Fateixa, S; Nogueira, HIS; Daniel-da-Silva, AL; Trindade, T
nossos autores
Ana Luísa Daniel da Silva
Investigador Principal
Helena Isabel Seguro Nogueira
Professor Auxiliar com Agregação
João Tiago Moniz Fernandes
Estudante de doutoramento
Natércia da Conceição Tomé Martins
Investigador Júnior
Sara Fateixa
Investigador Júnior
Tito Trindade
Professor Catedráticoagradecimentos
T.F. thanks the FundacAo para a Ciencia e Tecnologia (FCT) for the PhD grant SFRH/BD/130934/2017. N.C.T.M. and S.F. are funded by national funds (OE) , through FCT-FundacAo para a Ciencia e Tec-nologia,I.P., in the scope of the framework contract foreseen in the numbers 4, 5, and 6 of the article 23, of the Decree-Law 57/2016, of August 29, changed by the law 57/2017, of July 19. A. L. D. Silva acknowledges FCT for the research contract under the Program 'Investigador FCT' 2014. This work was developed within the scope of the project CICECO-Aveiro Institute of Materials, FCT Ref. UIDB/50011/2020 & UIDP/50011/2020.