Microrheology

We use various types of microrheology. Amongst those are based on Diffusion Wave Spectroscopy (DWS), Dynamic Light Scattering (DLS) and Optical Tweezers (OT). In all methods light scattering from colloidal probe particles is recoded and subsequently processed. The scattered intensity- or position-autocorrelation functions are directly related to the equilibrium viscoelastic properties, such as the vicous (loss) modulus and the elastic modulus of the surrounding liquid. These quantities can be measured in the frequency range of 1 Hz- 1 MHz. We use the DWS Rheolab from LS Instruments.

During his PhD in the Eiser group at the Cavendish Laboratory, Cambridge, UK, Alessio Cacciagli developed microrheology using DLS in back-scattering mode. This approch can be used with any light-scattering device. Alessio developed a Matlab code to analyze the scattering auto-correlation function using a regularization thechnique. This technique can also be applied to DWS data and particle-tracking measurements. An overview over the diffenrent techniques can be found here.

Page updated

Google Sites

Report abuse