Wei Wang tells Soft Matter about his hot communication.

Could you explain the significance of your article to the non-specialist?
Investigations on supramolecular aggregates which form vesicles and eventually cells have attracted a great deal of interest from scientists who work in biology, biophysics, biochemistry, chemistry, theoretical physics, and mathematics. Our work presents a first step in constructing and controlling molecular shapes via block codendrimers. The work presented may lead to the ability to manipulate the size and topological shape of aggregates. The topological transformation of aggregates has been successfully explained according to Helfrich's theory based on the bending free energy of membranes. Our work reveals a path that allows chemists to obtain the targeted supramolecular objects and allows biologists to modify cells by tailoring the size and shape of the hydrophobic and hydrophilic parts of amphiphiles.  

What has motivated you to conduct this work?
It is well known that amphiphilic molecules or block copolymers can form special aggregates, like micelles or vesicles, in selected solvents. With a better understanding of the relation between molecular shape and topological structure of supramolecular aggregates, initiated by Israelachvili and others, we believe that block codendrimers are a novel system which has advantages of both amphiphilic molecules and block copolymers. This is because the molecular shape can be easily tuned by changing the generation of the individual dendrons and functional groups can be precisely placed on the dendron periphery. Interestingly, Helfrich's theory based on bending free energy of membranes successfully explained the topological transformation of aggregates from spheres via toroids to button-like structures. 

Where do you see this work developing in the future?
Amphiphilic block copolymers have been used in cell manipulations. The normal block copolymers are polydisperse and their length is much larger than the thickness of cell membranes. These disadvantages may limit their application in future studies. Amphiphilic block codendrimers synthesized in our group have a well-defined 3D shape, multi-functional groups in the inner or on the periphery of dendrons, and a molecular size similar to the thickness of cell membranes. We think they can be used in biological studies in the future. 

Are there any particular challenges facing future research in this area?
We are planning to apply our special molecules in biology. One of the difficult challenges for us is to correctly select biological targets as well as to successfully synthesize bio-compatible codendrimers. We will be actively seeking to collaborate with bioscientists.