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  • Synthesis and SERS application of gold and iron oxide functionalized bacterial cellulose nanocrystals (Au@Fe 3 O 4 @BCNCs)
Title: Synthesis and SERS application of gold and iron oxide functionalized bacterial cellulose nanocrystals (Au@Fe 3 O 4 @BCNCs)
Bacterial cellulose nanocrystals (BCNCs) are biocompatible cellulose nanomaterials that can host guest nanoparticles to form hybrid nanocomposites with a wide range of applications. Herein, we report the synthesis of a hybrid nanocomposite that consists of plasmonic gold nanoparticles (AuNPs) and superparamagnetic iron oxide (Fe 3 O 4 ) nanoparticles supported on BCNCs. As a proof of concept, the hybrid nanocomposites were employed to isolate and detect malachite green isothiocyanate (MGITC) via magnetic separation and surface-enhanced Raman scattering (SERS). Different initial gold precursor (Au 3+ ) concentrations altered the size and morphology of the AuNPs formed on the nanocomposites. The use of 5 and 10 mM Au 3+ led to a heterogenous mix of spherical and nanoplate AuNPs with increased SERS enhancements, as compared to the more uniform AuNPs formed using 1 mM Au 3+ . Rapid and sensitive detection of MGITC at concentrations as low as 10 −10 M was achieved. The SERS intensity of the normalized Raman peak at 1175 cm −1 exhibited a log-linear relationship for MGITC concentrations between 2 × 10 −10 and 2 × 10 −5 M for Au@Fe 3 O 4 @BCNCs. These results suggest the potential of these hybrid nanocomposites for application in a broad range of analyte detection strategies.  more » « less
Award ID(s):
1705653 2029911
PAR ID:
10180016
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
The Analyst
Volume:
145
Issue:
12
ISSN:
0003-2654
Page Range / eLocation ID:
4358 to 4368
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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