Colloidal aggregation and critical Casimir forces - Reply

In a recent Letter [Phys. Rev. Lett. 103, 156101 (2009)], we presented experiments on critical Casimir induced colloidal aggregation in a system with negligibly small van der Waals forces. We presented a simple model based on a competition between repulsive electrostatic and attractive critical Casimir forces to account for the observed aggregation. A recent comment [A. Gambassi, S. Dietrich, arXiv:1006.5897v1] proposed that the simple model should be regarded with caution as to its domain of application, and that it can be refined in a number of different ways. Here, we revisit our experimental finding and give a reply to the comment.