https://doi.org/10.1140/epjst/e2011-01509-9
Regular Article
Kinetics of colloidal fractal aggregation by differential dynamic microscopy
1 Dipartimento di Fisica e Matematica, Università degli Studi dell’Insubria, via Valleggio 11, 22100 Como, Italy
2 School of Physics and Astronomy, University of Glasgow, Glasgow, G12 8QQ, UK
3 Centre de Physique Théorique, École Polytechnique, Centre National de la Recherche Scientifique, 91128 Palaiseau, France
4 Institut National de la Recherche Scientifique-Énergie, Matériaux et Télécommunications, 1650, boulevard Lionel-Boulet EMT, Varennes, QC, J3X 1S2, Canada
5 Dipartimento di Chimica, Biochimica e Biotecnologie per la Medicina, Università degli Studi di Milano, via F.lli Cervi 93, 20090 Segrate, Italy
a e-mail: roberto.cerbino@unimi.it
Received:
29
August
2011
Revised:
4
October
2011
Published online:
7
December
2011
We study the kinetics of an aggregation process induced by adding salt to a stable colloidal suspension of 73 nm (diameter) particles. Despite the subdiffraction size of the colloidal particles, the process is monitored via optical microscopy, which is used here to obtain time-resolved scattering information about the colloidal aggregates. The radius of the aggregates is determined as a function of time and their fractal dimension is extracted. Our results are compatible with a diffusion limited aggregation process, as independently confirmed by spectral turbidimetry measurements on the same sample.
© EDP Sciences, Springer-Verlag, 2011
