Variable temperature, relative humidity (0%–100%), and liquid neutron reflectometry sample cell suitable for polymeric and biomimetic materials
Harroun, T.A.; Fritzsche, H.; Watson, M.J.; Yager, K.G.; Tanchak, O.M.; Barrett, C.J.; Katsaras, J. "Variable temperature, relative humidity (0%–100%), and liquid neutron reflectometry sample cell suitable for polymeric and biomimetic materials" Review of Scientific Instruments 2005
Two prototype sample cells were designed, built, and tested. These cells enable neutron reflectometry experiments to be carried out on samples in a controlled humid air environment, and in a bulk liquid environment. This is especially relevant for biologically-interesting samples.
We describe a variable temperature, relative humidity (0%–100% RH), and bulk liquid neutron reflectometry sample cell suitable for the study of polymeric and biomimetic materials (e.g., lipid bilayers). Compared to previous reflectometry cells, one of the advantages of the present sample environment is that it can accommodate ovens capable of handling either vapor or bulk liquid hydration media. Moreover, the design of the sample cell is such that temperature gradients are minimal over a large area (~80 cm2) allowing for the nontrivial 100% RH condition to be attained. This permits the study, by neutron reflectometry, of samples that are intrinsically unstable in bulk water conditions, and is demonstrated by the lamellar repeat spacing of lipid bilayers at 100% RH being indistinguishable from those same bilayers hydrated in liquid water.