The relationship between a dried and native steroid gel

Abstract

Steroid/cyclohexane gels are dried and observed by the shadowing replication electron microscopy technique. Two very different kinds of images are obtained: quasi-infinite connected filaments and isolated small filaments. In both cases, helical pitches and diameters of twisted fibers are respectively ∼58 and 25 nm. Results are compared with those of the native gels from freeze-etching replication electron microscopy and SANS techniques which show helical filaments about 9 nm in diameter. The modification in the filament structure of the dried gel is interpreted as being an intrinsic property of the chiral native filaments.