Size Distribution of Gold Nanoparticles Used by Small Angle X-ray Scattering

Abstract

The size distribution of gold nanoparticles was estimated based on the scattering intensity data obtained from small angle X-ray scattering (SAXS) and compared with the result of micrographs by transmission electron microscopy. The slope of the Guinier plot was used to estimate the mean size assuming a narrow particle size distribution. When the size distribution is narrow, the mean size can be easily obtained from slope of a Guinier plot of scattering data within 10% error. Additionally, assuming a lognormal size distribution, the size distribution and the mean size can be calculated using the experimental SAXS data in the fitting analysis. The histogram method, which utilizes the coefficient matrix of scattering intensity, was also applied to the estimation of the size distribution, and this method could be useful for a rough estimate of the size distribution.

Comparison of Nanometric Particle Size Distributions as Determined by SAXS, TEM and Analytical Ultracentrifuge

“…The latter technique has several advantages compared with the others. SAXS can be used for analyzing aerosols as well as dispersions and powders [8][9][10][11][12][13][14] whereas dynamic light scattering and AUC can be used only for dispersions and differential mobility analysis only for aerosols. In the case of aggregated samples, it is possible to determine the mean diameter of the agglomerates and also the mean diameter of the primary particles by SAXS [9], which is not possible with the measurement techniques mentioned earlier.…”

“…Moreover, there is no limitation imposed by drying or mounting the sample, which can lead to aggregation or other physical change. In recent years many approaches have been developed to determine particle size distributions from SAXS data by assuming Gaussian and/or log normal distributions [9,12,13] and the maximum entropy method (MEM) [15][16][17]. In this paper particle size distributions from the scattering curves of two colloidal, non-aggregated suspensions are determined.…”

Nanomaterials

“…51,52 SAXS has been used to measure the size of Au NM, with a larger size measured in comparison to TEM as SAXS is again sensitive to the 6th power of the particle diameter (d 6 ). 53 Furthermore, SAXS has been used to infer the aggregation state of Ag NM synthesized using reducing and capping agents. 51 SAXS is however limited by the need to fit and model scattering data 52,53 and is often conducted at a synchrotron.…”

“…53 Furthermore, SAXS has been used to infer the aggregation state of Ag NM synthesized using reducing and capping agents. 51 SAXS is however limited by the need to fit and model scattering data 52,53 and is often conducted at a synchrotron. 51,52 Also, scattering of NM dispersions in biological or environmental media can be dominated by the liquid (and other components in the medium), creating issues for measurement of small NM sizes and dilute concentrations.…”

Analysis and Characterization of Manufactured Nanoparticles in Aquatic Environments

“…Small angle X -ray scattering (SAXS) uses similar principles to static or dynamic light scattering but the particle sizes that can be probed are much lower ( ∼ 1 -50 nm) than for these due to the lower wavelength of X -ray light (Waychunas et al , 2005 ;Megens et al , 1997 ;Mori et al , 2006 ). There are laboratory versions available but these generally provide too low X -ray intensity for characterization of nanoparticles.…”