Golden fullerenes have recently been identified by photoelectron spectra by Bulusu et al. [S. Bulusu, X. Li, L.-S. Wang, X. C. Zeng, PNAS 2006, 103, 8326-8330]. These unique triangulations of a sphere are related to fullerene duals having exactly 12 vertices of degree five, and the icosahedral hollow gold cages previously postulated are related to the Goldberg-Coxeter transforms of C20 starting from a triangulated surface (hexagonal lattice, dual of a graphene sheet). This also relates topologically the (chiral) gold nanowires observed to the (chiral) carbon nanotubes. In fact, the Mackay icosahedra well known in gold cluster chemistry are related topologically to the dual halma transforms of the smallest possible fullerene C20 . The basic building block here is the (111) fcc sheet of bulk gold which is dual to graphene. Because of this interesting one-to-one relationship through Euler's polyhedral formula, there are as many golden fullerene isomers as there are fullerene isomers, with the number of isomers Niso increasing polynomially as O(Niso9 ). For the recently observed Au16- , Au17- , and Au18- we present simulated photoelectron spectra including all isomers. We also predict the photoelectron spectrum of Au32- . The stability of the golden fullerenes is discussed in relation with the more compact structures for the neutral and negatively charged Au12 to Au20 and Au32 clusters. As for the compact gold clusters we observe a clear trend in stability of the hollow gold cages towards the (111) fcc sheet. The high stability of the (111) fcc sheet of gold compared to the bulk 3D structure explains the unusual stability of these hollow gold cages.
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http://dx.doi.org/10.1002/chem.201601239 | DOI Listing |
Anal Chim Acta
February 2025
College of Food Science and Technology, Henan Key Laboratory of Cereal and Oil Food Safety Inspection and Control, Henan University of Technology, Zhengzhou, 450001, China.
Background: Aflatoxin B1 (AFB1) is a secondary metabolite produced by Aspergillus flavus and Aspergillus parasiticus. This toxin is highly carcinogenic and toxic, posing a serious threat to human and animal health. AFB1 primarily enters the human body through contaminated food, particularly peanuts, corn, nuts, and wheat.
View Article and Find Full Text PDFSci Rep
January 2025
Laser and Plasma Research Institute, Shahid Beheshti University, Tehran, Iran.
A localized surface plasmon resonance (LSPR) sensor based on tapered optical fiber (TOF) using hollow gold nanoparticles (HAuNPs) for measuring the refractive index (RI) is presented. This optical fiber sensor is a good candidate for a label-free RI biosensor. In practical biosensors, bioreceptors are immobilized on nanoparticles (NPs) that only absorb specific biomolecules.
View Article and Find Full Text PDFOsteoarthritis, a major global cause of pain and disability, is driven by the irreversible degradation of hyaline cartilage in joints. Cartilage tissue engineering presents a promising therapeutic avenue, but success hinges on replicating the native physiological environment to guide cellular behavior and generate tissue constructs that mimic natural cartilage. Although electrical stimulation has been shown to enhance chondrogenesis and extracellular matrix production in 2D cultures, the mechanisms underlying these effects remain poorly understood, particularly in 3D models.
View Article and Find Full Text PDFFood Chem X
January 2025
College of Food Science and Engineering, Wuhan Polytechnic University, Wuhan 430023, China.
ACS Appl Mater Interfaces
January 2025
School of Chemical and Biological Engineering, Institute of Engineering Research, College of Engineering, Seoul National University, Seoul 08826, Republic of Korea.
Stable hollow-type microspheres (MSs) have been fabricated using α-synuclein (αS), an amyloidogenic protein, via freeze-induced protein self-assembly. This assembly process involves three steps: rapid freezing to form spherical protein condensates from αS oligomers, frozen annealing to form a crust on the condensate and freeze-drying to create an interior lumen via the three-dimensional (3D) coffee-stain effect. The crust produced during the frozen-annealing step is a β-sheet-mediated protein structure that is presumed to be created at the quasi-liquid layer of the protein-ice interface and thus contributes to the stability of MSs in aqueous solutions at room temperature without any additional surface stabilization.
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