Alan W. Szmodis, Craig D. Blanchette, Andrey A. Levchenko, Alexandra Navrotsky, Marjorie L. Longo, Christine A. Orme, and Atul N. Parikh Soft Matter 4, 1161 - 1164, 2008

Via imaging ellipsometry, we study the phase transition dynamics induced by selective gelation of one component in a binary supported phopholipid bilayer. We find the modulation of two attendant morphological features: emergence of extended defect chains due to a net change in the molecular areas and fractal-like domains suggesting weak line tension. A time-lapse analysis of the ellipsometric images reveals the cluster size of 4–20 molecules undergoing gelation indicating weak cooperativity. These results demonstrate the use of ellipsometry for in situ, label-free, non-contact, and large-area imaging of dynamics in interfacial films.