Controlled Aggregation of Citrate-Stabilized Gold Nanoparticles into Long-Lived Metastable Clusters.
- 1Laboratory of Molecular Spectroscopy, Department of Fundamental Chemistry, Institute of Chemistry, University of São Paulo, Avenida Professor Lineu Prestes, 748, São Paulo, São Paulo CEP05508-000, Brazil.
Abstract
The controlled aggregation of plasmonic nanoparticles remains a critical challenge for achieving temporally stable and reproducible colloidal substrates for surface-enhanced Raman scattering (SERS). Here, we show that the antihistamine drug bilastine induces a concentration-dependent, self-limiting aggregation of citrate-capped gold nanoparticles (cit-AuNPs), producing long-lived metastable clusters in aqueous media. UV-Vis spectroscopy reveals the emergence and temporal evolution of a lower-energy, plasmon-coupling band, while dynamic light scattering (DLS) supports the formation of larger colloidal structures in suspension. Transmission electron microscopy (TEM) provides complementary qualitative evidence of concentration dependent changes in aggregate morphology. Zeta potential measurements show progressive interfacial charge regulation upon bilastine addition, consistent with perturbation of the citrate-stabilized interface. SERS spectra and citrate-control experiments support the presence of bilastine in the SERS-active interfacial region, with enhanced carboxylate-associated modes suggesting proximity of the carboxylate-containing region to the Au surface. Time-dependent optical measurements and semi-quantitative DLVO-type analysis indicate a slowly evolving, self-limiting aggregation regime at selected submicromolar bilastine concentration, whereas higher concentrations promote faster destabilization. The resulting aggregates retain SERS activity over extended periods, highlighting bilastine as a molecular modulator for generating long-lived SERS-active AuNP clusters.
Related
- Gas-Phase Reactivity of AuSiO3– Anion Clusters with n-Alkanes (C1–C4): Distinguishing Capture, Stabilized Association, and C–H Bond Activation
- Metal‐Organic Framework‐Derived Metastable Cu2ZnSnS4/ZnS Heterojunction Realizes Kinetic‐Controlled Lattice Strain Engineering and Built‐In Electric Field Synergistically Enhanced Microwave Absorption
- The Core Matters: Aggregation of Neutral Ligand-Coated Nanoparticles in Membranes
- Substituent‐Dependent SERS Kinetics of Citrate‐Stabilized Gold Nanoparticles: Balancing Hotspot Formation and Colloidal Flocculation
- Axially Chiral ( R )-BINOL-, ( R )-BINAM-, and ( R )-NOBIN-Stabilized Palladium Nanoparticles for Highly Enantioselective Asymmetric Suzuki-Miyaura Cross-Coupling Reactions
BibTeX
@article{oliveira2026controlled,
title = {{Controlled Aggregation of Citrate-Stabilized Gold Nanoparticles into Long-Lived Metastable Clusters.}},
author = {Maelly A Oliveira and Rômulo A Ando},
journal = {Langmuir : the ACS journal of surfaces and colloids},
year = {2026},
month = sep,
doi = {10.1021/acs.langmuir.6c03197},
url = {https://europepmc.org/article/MED/42916778},
note = {CC BY},
}
RIS
TY - JOUR
TI - Controlled Aggregation of Citrate-Stabilized Gold Nanoparticles into Long-Lived Metastable Clusters.
AU - Maelly A Oliveira
AU - Rômulo A Ando
PY - 2026
DA - 2026/09/01
JO - Langmuir : the ACS journal of surfaces and colloids
DO - 10.1021/acs.langmuir.6c03197
UR - https://europepmc.org/article/MED/42916778
AB - The controlled aggregation of plasmonic nanoparticles remains a critical challenge for achieving temporally stable and reproducible colloidal substrates for surface-enhanced Raman scattering (SERS). Here, we show that the antihistamine drug bilastine induces a concentration-dependent, self-limiting aggregation of citrate-capped gold nanoparticles (cit-AuNPs), producing long-lived metastable clusters in aqueous media. UV-Vis spectroscopy reveals the emergence and temporal evolution of a lower-energy, plasmon-coupling band, while dynamic light scattering (DLS) supports the formation of larger colloidal structures in suspension. Transmission electron microscopy (TEM) provides complementary qualitative evidence of concentration dependent changes in aggregate morphology. Zeta potential measurements show progressive interfacial charge regulation upon bilastine addition, consistent with perturbation of the citrate-stabilized interface. SERS spectra and citrate-control experiments support the presence of bilastine in the SERS-active interfacial region, with enhanced carboxylate-associated modes suggesting proximity of the carboxylate-containing region to the Au surface. Time-dependent optical measurements and semi-quantitative DLVO-type analysis indicate a slowly evolving, self-limiting aggregation regime at selected submicromolar bilastine concentration, whereas higher concentrations promote faster destabilization. The resulting aggregates retain SERS activity over extended periods, highlighting bilastine as a molecular modulator for generating long-lived SERS-active AuNP clusters.
SN - 0743-7463
SN - 1520-5827
ER -