Biomaterial Database

Particle sizing by dynamic light scattering: non-linear cumulant analysis. 2015

Alastair G Mailer, and Paul S Clegg, and Peter N Pusey

SUPA, School of Physics and Astronomy, University of Edinburgh, Peter Guthrie Tait Road, Edinburgh, EH9 3FD, UK.

We revisit the method of cumulants for analysing dynamic light scattering data in particle sizing applications. Here the data, in the form of the time correlation function of scattered light, is written as a series involving the first few cumulants (or moments) of the distribution of particle diffusion constants. Frisken (2001 Appl. Opt. 40 4087) has pointed out that, despite greater computational complexity, a non-linear, iterative, analysis of the data has advantages over the linear least-squares analysis used originally. In order to explore further the potential and limitations of cumulant methods we analyse, by both linear and non-linear methods, computer-generated data with realistic 'noise', where the parameters of the distribution can be set explicitly. We find that, with modern computers, non-linear analysis is straightforward and robust. The mean and variance of the distribution of diffusion constants can be obtained quite accurately for distributions of width (standard deviation/mean) up to about 0.6, but there appears to be little prospect of obtaining meaningful higher moments.

UI	MeSH Term	Description	Entries
D010316	Particle Size	Relating to the size of solids.	Particle Sizes,Size, Particle,Sizes, Particle
D004058	Diffusion	The tendency of a gas or solute to pass from a point of higher pressure or concentration to a point of lower pressure or concentration and to distribute itself throughout the available space. Diffusion, especially FACILITATED DIFFUSION, is a major mechanism of BIOLOGICAL TRANSPORT.	Diffusions
D000067493	Dynamic Light Scattering	An analytical technique for measuring particle size of molecules that are less than a micron in diameter dispersed or dissolved in a liquid.	Quasi-Elastic Light Scattering (QELS),Light Scattering, Dynamic,Light Scattering, Quasi-Elastic (QELS),Quasi Elastic Light Scattering (QELS),Quasi-Elastic Light Scatterings (QELS),Scattering, Dynamic Light,Scattering, Quasi-Elastic Light (QELS),Scatterings, Quasi-Elastic Light (QELS)
D013223	Statistics as Topic	Works about the science and art of collecting, summarizing, and analyzing data that are subject to random variation.	Area Analysis,Estimation Technics,Estimation Techniques,Indirect Estimation Technics,Indirect Estimation Techniques,Multiple Classification Analysis,Service Statistics,Statistical Study,Statistics, Service,Tables and Charts as Topic,Analyses, Area,Analyses, Multiple Classification,Area Analyses,Classification Analyses, Multiple,Classification Analysis, Multiple,Estimation Technic, Indirect,Estimation Technics, Indirect,Estimation Technique,Estimation Technique, Indirect,Estimation Techniques, Indirect,Indirect Estimation Technic,Indirect Estimation Technique,Multiple Classification Analyses,Statistical Studies,Studies, Statistical,Study, Statistical,Technic, Indirect Estimation,Technics, Estimation,Technics, Indirect Estimation,Technique, Estimation,Technique, Indirect Estimation,Techniques, Estimation,Techniques, Indirect Estimation
D016014	Linear Models	Statistical models in which the value of a parameter for a given value of a factor is assumed to be equal to a + bx, where a and b are constants. The models predict a linear regression.	Linear Regression,Log-Linear Models,Models, Linear,Linear Model,Linear Regressions,Log Linear Models,Log-Linear Model,Model, Linear,Model, Log-Linear,Models, Log-Linear,Regression, Linear,Regressions, Linear
D017711	Nonlinear Dynamics	The study of systems which respond disproportionately (nonlinearly) to initial conditions or perturbing stimuli. Nonlinear systems may exhibit "chaos" which is classically characterized as sensitive dependence on initial conditions. Chaotic systems, while distinguished from more ordered periodic systems, are not random. When their behavior over time is appropriately displayed (in "phase space"), constraints are evident which are described by "strange attractors". Phase space representations of chaotic systems, or strange attractors, usually reveal fractal (FRACTALS) self-similarity across time scales. Natural, including biological, systems often display nonlinear dynamics and chaos.	Chaos Theory,Models, Nonlinear,Non-linear Dynamics,Non-linear Models,Chaos Theories,Dynamics, Non-linear,Dynamics, Nonlinear,Model, Non-linear,Model, Nonlinear,Models, Non-linear,Non linear Dynamics,Non linear Models,Non-linear Dynamic,Non-linear Model,Nonlinear Dynamic,Nonlinear Model,Nonlinear Models,Theories, Chaos,Theory, Chaos