Related Experiment Video

Updated: Jan 20, 2026

Engineering Molecular Recognition with Bio-mimetic Polymers on Single Walled Carbon Nanotubes

Engineering Molecular Recognition with Bio-mimetic Polymers on Single Walled Carbon Nanotubes

Published on: January 10, 2017

Chiral Imidazolium-Functionalized Au Nanoparticles: Reversible Aggregation and Molecular Recognition

Diego Alberto Lomelí-Rosales¹, Irma Idalia Rangel-Salas¹, Adalberto Zamudio-Ojeda¹

¹Departamento de Química, Centro Universitario de Ciencias Exactas e Ingenierías and Departamento de Física, Centro Universitario de Ciencias Exactas e Ingenierías, Universidad de Guadalajara, Blvd. Marcelino García Barragán #1421, esq. Olímpica, C.P. 44430 Guadalajara, Jalisco, Mexico.

|August 29, 2019

Summary

Amino acid-derived imidazolium salts stabilize gold nanoparticles (AuNPs). The methionine-derived salt provided excellent dispersion and pH-dependent aggregation, enabling chiral recognition and racemic mixture separation.

Area of Science:

Materials Science
Nanotechnology
Supramolecular Chemistry

Background:

Gold nanoparticles (AuNPs) are versatile nanomaterials with applications in catalysis, sensing, and drug delivery.
Stabilization of AuNPs is crucial for maintaining their properties and preventing aggregation.
Amino acid-derived compounds offer potential as biocompatible and tunable stabilizing agents.

Purpose of the Study:

To synthesize and characterize gold nanoparticles (AuNPs) stabilized by novel imidazolium salts derived from amino acids.
To investigate the effect of different amino acid-derived stabilizers on AuNP dispersion, stability, and aggregation behavior.
To explore the potential of these functionalized AuNPs in chiral recognition and separation applications.

Main Methods:

Synthesis of gold nanoparticles using four different amino acid-derived imidazolium salts (glycine, alanine, phenylalanine, methionine).
Characterization of AuNPs using UV-Vis spectroscopy and particle size analysis.
Investigation of pH-dependent aggregation and reversibility of the stabilized AuNPs.
Synthesis of chiral AuNPs and confirmation of surface chirality using circular dichroism.
Evaluation of molecular recognition capabilities and separation of racemic mixtures on a layered double hydroxide support.

Main Results:

AuNPs stabilized by the methionine-derived imidazolium salt (4-AuNPs) exhibited superior stability in water (pH > 5.5) for extended periods.
The 4-AuNPs showed a characteristic absorption band at 517 nm with an average particle size of 11.21 ± 0.07 nm.
Reversible aggregation of 4-AuNPs was achieved by controlling solution pH.
Chiral R,R-4-AuNPs and S,S-4-AuNPs demonstrated molecular recognition of chiral substrates.
The functionalized AuNPs showed promise for separating racemic mixtures when immobilized on layered double hydroxide.

Conclusions:

Amino acid-derived imidazolium salts are effective stabilizers for gold nanoparticles.
The methionine-derived salt offers excellent colloidal stability and pH-responsive aggregation control.
Chiral AuNPs synthesized using this method exhibit enantioselective recognition and can be utilized for racemic mixture separation.

More Related Videos

Reverse Microemulsion-mediated Synthesis of Monometallic and Bimetallic Early Transition Metal Carbide and Nitride Nanoparticles

Reverse Microemulsion-mediated Synthesis of Monometallic and Bimetallic Early Transition Metal Carbide and Nitride Nanoparticles

Published on: November 27, 2015

Biofunctionalized Prussian Blue Nanoparticles for Multimodal Molecular Imaging Applications

Biofunctionalized Prussian Blue Nanoparticles for Multimodal Molecular Imaging Applications

Published on: April 28, 2015

Related Concept Videos

Chirality

Chirality

Chirality is a term that describes the lack of mirror symmetry in an object. In other words, chiral objects cannot be superposed on their mirror images. For example, our feet are chiral, as the mirror image of the left foot, the right foot, cannot be superposed on the left foot.
Chiral objects exhibit a sense of handedness when they interact with another chiral object. For example, our left foot can only fit in the left shoe and not in the right shoe. Achiral objects — objects that have...

Chirality in Nature

Chirality in Nature

Chirality is the most intriguing yet essential facet of nature, governing life’s biochemical processes and precision. It can be observed from a snail shell pattern in a macroscopic world to an amino acid, the minutest building block of life. Most of the snails around the world have right-coiled shells because of the intrinsic chirality in their genes. All the amino acids present in the human body exist in an enantiomerically pure state, except for glycine - the sole achiral amino acid.

Molecules with Multiple Chiral Centers

Molecules with Multiple Chiral Centers

Molecules that possess multiple chiral centers can afford a large number of stereoisomers. For instance, while some molecules like 2-butanol have one chiral center, defined as a tetrahedral carbon atom with four different substituents attached, several molecules like butane-2,3-diol have multiple chiral centers. A simple formula to predict the number of stereoisomers possible for a molecule with n chiral centers is 2n. However, there can be a lower number where some of the stereoisomers are...

Chirality at Nitrogen, Phosphorus, and Sulfur

Chirality at Nitrogen, Phosphorus, and Sulfur

Chirality is most prevalent in carbon-based tetrahedral compounds, but this important facet of molecular symmetry extends to sp3-hybridized nitrogen, phosphorus and sulfur centers, including trivalent molecules with lone pairs. Here, the lone pair behaves as a functional group in addition to the other three substituents to form an analogous tetrahedral center that can be chiral.
A consequence of chirality is the need for enantiomeric resolution. While this is theoretically possible for all...

Molecular Chaperones and Protein Folding

Molecular Chaperones and Protein Folding

The native conformation of a protein is formed by interactions between the side chains of its constituent amino acids. When the amino acids cannot form these interactions, the protein cannot fold by itself and needs chaperones. Notably, chaperones do not relay any additional information required for the folding of polypeptides; the native conformation of a protein is determined solely by its amino acid sequence. Chaperones catalyze protein folding without being a part of the folded protein.
The...

Molecular Orbital Theory I

Molecular Orbital Theory I

Overview of Molecular Orbital Theory

Articles linked to this work by shared authors, journal, and citation graph.

Molecular Imprinting of Phosphate Moieties into the Silica Matrix as a Novel Phosphorus Rechargeable System for Copper Ions Adsorption.

Polymers·2026

Experimental and Computational Insights into the Apoptotic Potential of New Phenanthroline-Based Copper(II) Complexes: From Spectroscopic Characterization and In Vitro Cytotoxicity to In Silico Target Identification.

Biomedicines·2026

A novel activity of chitosan nanoparticles as an enhancer of biofilm formation in resistant Diarrheagenic Escherichia coli strains.

Carbohydrate research·2026

A Chemical Approach to the Synthesis of an Antitumoral Pt-Based Drug Molecule Using a Protein-Ligand Interaction as a Carrier System.

ACS omega·2026

Hass Avocado Bioactive Compounds Attenuating Oxidative Stress and Inflammation in Ischemia-reperfusion Injury: An Integrative Review.

Plant foods for human nutrition (Dordrecht, Netherlands)·2026

Structural studies, thermochromic luminescent properties and crystal-to-crystal transformation of a double-stranded CuI-I-bisquinoline coordination polymer.

RSC advances·2026

See all related articles