Self-assembled fibrillar networks induced by two methods: a new unmodified natural product gel

Abstract

To date, low molecular weight gels based on natural products have attracted much attention due to their excellent biological activities. Recently, some natural products with new features (e.g., natural product gelators, NPGs) have been reported to directly self-assemble in different solvents to form soft material-gels, i.e., natural product gels. Unlike synthetic low molecular weight gelators, NPGs come from organisms and therefore, their structures and properties are unknown. Herein, a general and efficient method for obtaining NPGs from organisms, which provides specific and important guidance for researchers to easily discover new NPGs from organisms, has been reported. We report a new NPG, β-sitosterol (Sito), isolated from Arisaema heterophyllum Blume. SEM, UV-vis, FT-IR, CAT (contact angle text), XRD, and theoretical calculations were used to explain the properties, morphology, driving force, and molecular packing models of the gels. Sito self-assembled into different fibrillar networks via heat–cool and ultrasound methods. Then, we demonstrated that hydrogen bonding plays a major role in the formation of these nanoaggregates. In addition, in vitro experiments showed that the nanoaggregates have similar or better ability to inhibit the growth of cancer cells as Sito. Therefore, the Sito nanoaggregates are expected to be potential drug delivery materials.