resumo
A simple method based on sucrose density gradient centrifugation is proposed here for the fractionation of colloidal silver nanotriangles. This method afforded particle fractions with surface plasmon resonances, spanning from red to infrared spectral ranges that could be used to tune optical properties for plasmonic applications. This feature was exemplified by selecting silver nanotriangle samples with spectral overlap with Atto-655 dye's absorption and emission in order to assemble dye-particle plasmophores. The emission brightness of an individual plasmophore, as characterized by fluorescence correlation spectroscopy, is at least 1000-fold more intense than that of a single Atto-655 dye label, which renders them as promising platforms for the development of fluorescence-based nanosensors.
palavras-chave
SINGLE-MOLECULE FLUORESCENCE; PLASMON-CONTROLLED FLUORESCENCE; GOLD NANOPARTICLES; ENHANCEMENT; EMISSION; PHOTOLUMINESCENCE; SEPARATION; PROTEIN; LIGHT
categoria
Science & Technology - Other Topics; Materials Science
autores
Oliveira-Silva, R; Sousa-Jeronimo, M; Botequim, D; Silva, NJO; Prazeres, DMF; Paulo, PMR
nossos autores
agradecimentos
This research was funded by FCT-Portuguese Foundation for Science and Technology, grant number UID/BIO/04565/2013 and UID/QUI/00100/2019; and Programa Operacional Regional de Lisboa 2020, grant number 007317. M.S.-J. would like to acknowledge the FCT project number 29460 (POCI-01-0145-FEDER-29460). R.O.-S. and D.B. would like to acknowledge the FCT program BIOTECnico fellowships PD/BD/116850/2016 and PD/BD/113630/2015, respectively.