Polymer-encapsulated gold or silver nanoparticles were synthesized and sterically stabilized by a shell layer of poly(4-vinylpyridine) (P4VP) grafted on SiO(2) nanoparticles that acts as a scaffold for the synthesis of hybrid noble metal nanomaterials. The grafting P4VP shell was synthesized via surface reversible addition-fragmentation chain transfer (RAFT) polymerization of 4-vinylpyridine (4VP) using SiO(2)-supported benzyl 9H-carbazole-9-carbodithioate (SiO(2)-BCBD) as the RAFT agent. The covalently tethered P4VP shell can coordinate with various transition metal ions such as Au(3+) or Ag(+) and therefore stabilize the corresponding Au or Ag nanoparticles reduced in situ by sodium borohydride (NaBH(4)) or trisodium citrate. The SiO(2)-supported RAFT agent and the Au or Ag nanoparticles embedded in the P4VP shell layer were characterized by UV-vis spectrophotometer, X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and surface-enhanced Raman spectroscopy (SERS).

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A novel and highly sensitive immunoassay method based on surface enhanced Raman spectroscopy (SERS) and magnetic particles has been developed. This method exhibits great potential application in bio-separation and immunoassay.

Over the last two decades, remarkable progress has been made in use of computational methods for understanding 2D materials growth. The aim of this Review is to provide an overview of several state-of-the-art computational methods for the modelling and simulation of 2D materials growth. First, the current status of 2D materials, and their major growth methods are addressed. Next, the applications of the ab initio method in 2D materials growth is discussed, focusing on reaction of precursors, diffusion of adatoms, energetics and kinetics of growth fronts, and effects of substrates. Then, the applications of the molecular dynamics approach in 2D materials growth is discussed, with emphasis on the growth of graphene on various substrates and the growth of boron nitride and silicene. Furthermore, the applications of the kinetic Monte Carlo method in 2D materials growth are discussed. The parametrization of the method and its application in dimer distribution, and nonlinear edge growth of graphene are discussed. Subsequently, the applications of the phase-field method in 2D materials growth are discussed, focusing on the growth rate and morphological evolution of 2D domains. Finally, perspectives and conclusions are presented.