Particle and Particle Systems Characterization:
Small-Angle Scattering (SAS) Applications
Small-angle scattering of UV radiation is typical of algae and plants chloroplast having ellipsoidal shape with diameter from 1 to 5 [micro]m and length from 1 [micro]m to 10 [micro]m [4].
This model is included in
small-angle scattering data analysis software packages such as the IGOR-based package used at the NIST Center for Neutron Research (14).
6-9) The size of the particles and the contrast provided by the electron density difference between latex particles and dispersion medium make
small-angle scattering techniques ideal for the structural analysis.
Among the topics are a single-molecule barcoding system using nanoslits for DNA analysis called nanocoding, inserting and manipulating DNA in a nanopore with optical tweezers, analyzing biomolecules using surface plasmons,
small-angle scattering and neutron contrast variation for studying biomolecular complexes, imaging quantum dots in vivo, the monitoring and affinity purification of proteins using dual tags with tetracysteine motifs, magnetic nanoparticles for local drug delivery using magnetic implants, and custom-designed molecular scissors for site-specific manipulation of the plant and mammalian genomes.
Guinier (20) introduced the concept of "particle scattering" where he demonstrated that a single colloidal particle could produce diffused X-ray
small-angle scattering, with a maximum at zero angles (21).
Figure 3 shows a combined plot of
small-angle scattering data obtained using light and x-ray instruments for one of the developmental samples.
Objective: Phase contrast and scattering-based (dark-field) X-ray imaging can potentially revolutionize the radiological approach to medical imaging because they are intrinsically capable of detecting subtle differences in the electron density of a material and of measuring the effective integrated local
small-angle scattering power generated by the microscopic density fluctuations in the specimen.
Other topics include enhancing properties through nanophased epoxy/foam, determining structure by
small-angle scattering, and applications in imaging and display media and as electrolytes in lithium batteries.
This evaluation follows the assumptions that the DMDBS molecules, which are miscible in the melt, contribute only to the background scattering, whereas the excess
small-angle scattering due to growth of DMDBS fibrils leads to an integrated intensity which is proportional to the (low) volume fraction of fibrils.
This will reduce systematic uncertainties associated with
small-angle scattering to the level of [10.
