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Morphological Programming in Gold(III) Coordination Assemblies via pH-Modulated Noncovalent Hierarchy.
Yelan Xiao1, Xiang Zhou1, Nuo Cheng1
1Shenzhen Key Laboratory for Nano-Biosensing Technology, Research Center for Biosensor and Nanotheranostic, School of Biomedical Engineering, Health Science Center, Shenzhen University, Shenzhen 518055, China.
ACS Applied Materials & Interfaces
|May 7, 2026
Summary
Researchers developed novel gold-nicotinamide complex nanospheres that reversibly change shape from spheres to cubes with pH changes. This discovery offers new design principles for smart organometallic nanomaterials.
Area of Science:
- Organometallic chemistry
- Nanomaterials science
- Supramolecular chemistry
Background:
- Gold-centered self-assemblies, including gold nanoparticles (AuNPs) and gold nanoclusters (AuNCs), have diverse applications.
- The use of Au(III) complexes as building blocks for self-assembled architectures is underexplored.
Purpose of the Study:
- To develop a facile self-assembly strategy using gold-nicotinamide complex as a building block.
- To construct uniform nanospheres with pH-responsive morphological switching.
Main Methods:
- Facile self-assembly strategy using gold-nicotinamide complex.
- pH stimulation via alkaline or acidic additions.
- Systematic experimental and theoretical calculations.
Main Results:
- Uniform nanospheres were constructed from gold-nicotinamide complex.
- Nanoparticles exhibited reversible disassembly and reassembly, switching from spheres to cubic nanoparticles upon pH stimulation.
- Driving forces identified as metal coordination and noncovalent interactions (π-π stacking, hydrogen bonding).
Conclusions:
- Established valuable design principles for stimuli-responsive organometallic nanomaterials.
- Highlighted the critical role of ligand architecture in controlling self-assembly behaviors.
- Demonstrated pH-mediated morphological switching in gold-nicotinamide nanomaterials.
Keywords:
Au(III)-nicotinamide complexnanoparticlesnoncovalent interactionspH stimulationself-assemblyMore Related Videos
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