A liposome (left) and dendrimersome. The blue parts of their molecules are hydrophilic, the green parts are hydrophobic.
Scientists continue to search out for new methods of smart delivery of drugs that can improve how meds are released and distributed. Researchers at University of Pennsylvania have taken lessons from how cells safely carry the contents within them in order to create new vesicles for drug delivery. The researchers used dendrimers, molecules that branch out repeatedly, to create concentric spheres of bilayers similar to cellular membranes. Any number of these spheres can be created together, one stuffed into the next like a matryoshka doll.
The advantage of such a design for drug delivery is that different drugs can be infused between the layers, being released in a pre-programmed fashion as the layers of the vesicle get broken down. Moreover, the same drug, placed within the layers at different concentrations, can be released at different rates as necessary.
From the study abstract in Proceedings of the National Academy of Sciences:
A constitutional isomeric library synthesized by a modular approach has been used to discover six amphiphilic Janus dendrimer primary structures, which self-assemble into uniform onion-like vesicles with predictable dimensions and number of internal bilayers. These vesicles, denoted onion-like dendrimersomes, are assembled by simple injection of a solution of Janus dendrimer in a water-miscible solvent into water or buffer. These dendrimersomes provide mimics of double-bilayer and multibilayer biological membranes with dimensions and number of bilayers predicted by the Janus compound concentration in water. The simple injection method of preparation is accessible without any special equipment, generating uniform vesicles, and thus provides a promising tool for fundamental studies as well as technological applications in nanomedicine and other fields.
Study in Proceedings of the National Academy of Sciences: Self-assembly of amphiphilic Janus dendrimers into uniform onion-like dendrimersomes with predictable size and number of bilayers…
Press release: Penn Research Develops ‘Onion’ Vesicles for Drug Delivery…
