Gold nanocluster properties exhibit unique size-dependence. In this contribution, we employ reactive molecular dynamics simulations to calculate the size- and temperature-dependent surface energies, strain energies and atomic displacements for icosahedral, cuboctahedral, truncated octahedral and decahedral Au-nanoclusters. The calculations demonstrate that the surface energy decreases with increasing cluster size at 0 K but increases with size at higher temperatures. The calculated melting curves as a function of cluster size demonstrate the Gibbs-Thomson effect. Atomic displacements and strain are found to strongly depend on the cluster size and both are found to increase with increasing cluster size. These results are of importance for understanding the size- and temperature-dependent surface processes on gold nanoclusters.

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The present study aims to synthesised nano gold with chemical method with two shape sphere and rod with multi diameter and aspect ratio and then characterize the synthesised material with Atomic Force Microscope (AFM), Transmission Electron Microscope (TEM) and Ultraviolet-visible (UV–Visible ) spectrophotometer. The AFM and TEM characterization result of three samples for each sphere and rods show that the synthesised material are in nano range with diameter 31.9 nm, 36.19 nm and 79.37 nm respectively for nano sphere and diameters 39.9nm, 36.05 nm and 28 nm respectively for nano-rods samples and the UV-Visible spectrophotometer show that peak of surface plasmon resonance of nano-sphere are at wavelengths 532 nm, 535 nm and 546 nm and all are in the visible range and nano-rod have two peaks one in the visible range at wavelengths 525nm,518nm and 531nm and the other peak is in the near infrared range at wavelengths 633nm, 680nm and 875 nm respectively.

Due to many problems associated with drug release and side effects, we could design a novel drug delivery system through modification of poly acrylic acid (AA) with Lactic acid as a spacer between the polymer and 4-aminoantipyrine. In vitro drug release had been conducted successfully in basic medium in pH 7.4 and acidic medium in pH 1.1 at 37℃. The prepared prodrug polymer was characterized by FTIR and 1 H−NMR spectra. Physical properties and intrinsic viscosity of drug polymer were determined. The good results were obtained in the presence of spacer unit with comparing without spacer unit.