Protein and Janus Particles properties using dielectrophoresis

This work determines the dielectrophoretic response of surface modified polystyrene and silica colloidal particles by experimentally measuring their Clausius-Mossotti factors. Commercial charged particles, fabricated ones coated with fibronectin, and Janus particles that have been grafted with fibronectin on one side only were investigated. We show that the dielectrophoretic response of such particles can be controlled by the modification of the chemistry or the anisotropy of their surface. Moreover, by modelling the polarizabilities of those particles, the dielectric parameters of the particles and the grafted layer of protein can be measured.DEPcolengineered

Selective grafting of Janus particle

Grafting of fibronectine (involved in cell adhesion process) was achieved on one side only of Au-PS or Au-SiO2 Janus particles. By combining selective chemistry on one side only, fibronectine (in red) was attached either on the PS side (in green) or SiO2 ( in orange) or on the Au side.

2 photon lithography of smart colloids

Successfully achieved 2 photon lithography process with a nanosecond visible laser of colloids. Those were fabricated with PEG and 4-HBA based resists. We have shown that the latter one can be displaced under a DC electric field. Colloidal particles were also manufactured : 10 um PS colloidal particle with a flagella.