resumo
Magnetite nanoparticles (MNPs) decorated with gold nanostars (AuNSs) have been prepared by using a seed growth method without the addition of surfactants or colloidal stabilizers. The hybrid nanomaterials were investigated as adsorbents for the uptake of tetracycline (TC) from aqueous solutions and subsequent detection using surface-enhanced Raman scattering (SERS). Several parameters were investigated in order to optimize the performance of these hybrid platforms on the uptake and SERS detection of TC, including variable pH values and the effect of contact time on the removal of TC. The spatial distribution of TC and AuNS on the hybrid composites was accomplished by coupling SERS analysis with Raman imaging studies, allowing also for the determination of the detection limit for TC when dissolved in ultrapure water (10 nM) and in more complex aqueous matrices (1 mu M). Attempts were also made to investigate the adsorption modes of the TC molecules at the surface of the metal NPs by taking into account the enhancement of the Raman bands in these different matrices.
palavras-chave
ENHANCED RAMAN-SPECTROSCOPY; SENSITIVE DETECTION; ANTIBIOTIC-RESIDUES; NANOPARTICLES; SILVER; SCATTERING; OXYTETRACYCLINE; ADSORPTION; ENRICHMENT; SEPARATION
categoria
Science & Technology - Other Topics; Materials Science
autores
Pinheiro, PC; Fateixa, S; Nogueira, HIS; Trindade, T
nossos autores
Helena Isabel Seguro Nogueira
Professor Auxiliar com Agregação
Paula Pinheiro
Bolseiro de investigação
Sara Fateixa
Investigador Júnior
Tito Trindade
Professor Catedráticoagradecimentos
This work was developed within the scope of the project CICECO-Aveiro Institute of Materials, POCI-01-0145-FEDER-007679 (FCT Ref. UID/CTM/50011/2013), and when appropriate co-financed by European Regional Development Fund (FEDER) under the PT2020 Partnership Agreement. P. C. Pinheiro thanks the Fundacao para a Ciencia e Tecnologia (FCT) for the PhD grant SFRH/BD/96731/2013. S. Fateixa thanks FCT for the grant SFRH/BPD/93547/2013.