INVESTIGADORES
MORENO Mario Sergio Jesus
artículos
Título:
Porphyrin‐conjugated silver‐coated gold nanostars for ultrasensitive detection and multiplexing
Autor/es:
BENAVIDES, LEANDRO N.; MORENO, M. SERGIO; MURGIDA, DANIEL H.; CASTRO, MARÍA A.
Revista:
JOURNAL OF RAMAN SPECTROSCOPY
Editorial:
JOHN WILEY & SONS LTD
Referencias:
Año: 2020 vol. 51 p. 2161 - 2170
ISSN:
0377-0486
Resumen:
Here, we propose the use of silver-coated gold nanostars as the basis for a multiplexsensing system based on surface-enhanced Raman scattering (SERS)/surface-enhanced resonance Raman scattering (SERRS) ultrasensitive detectionof porphyrins using a 532 nm laser excitation. By modifying the syntheticparameters, we were able to shift the plasmon peak to an optimized positionfor SERS enhancement of 540 nm for silver-coated gold nanostars, estimatinga SERS enhancement factor around 4.6 × 105. Furthermore, we show highresolutiontransmission electron microscopy (HR-TEM) images and electronenergy-loss (EEL) spectra of silver-coated gold nanostars, which provide solidexperimental proof on the proposed silver coating mechanism. Finally, wecompare the multiplex performance of common reporters such as cyaninesand malachite green with the performance of covalently bound porphyrinsand show the superiority of the latter. We studied the multiplex detectioncapabilities of the system with three different porphyrins. By deconvoluting amixture spectrum into individual porphyrin spectra, we were able to determinethe relative concentration of porphyrins with an average error of 3.1%.