University of New South Wales scientists has developed a way to control the shape of polymer molecules so that they self-assemble into non-spherical nanoparticles. The work was published yesterday in Nature Communications.
Polymersomes are polymer molecules that contain a water-soluble portion and a non-water-soluble portion, and which self-assemble into round, hollow structures. These polymersomes have been a great tool to deliver drugs because of their high stability, chemical versatility and the ease with which molecules on their surface can be altered.
In this study, the team was able to add a non-water-soluble perylene polymer group to the membrane of the polymersome. By doing this, the shape and the size of the polymersome can then be adjusted by changing the amount of water in the solvent.
Using cryogenic-transmission electron microscopy, the team was able to understand how the polymer molecules were packed together in solution.
"It's a straightforward but elegant solution which we feel has great potential for making a wide range of complex polymer structures inspired by nature," said Martina Stenzel, who is a co-supervisor of study's first author.
"Our breakthrough means we can predictably make smart polymers that shift their shape according to the different conditions around them to form tiny ellipsoidal or tubular structures that can encapsulate drugs. We have preliminary evidence that these more natural-shaped plastic nanoparticles enter tumor cells more easily than spherical ones," said senior author Pall Thordarson.
Image: Tubular shaped polymersomes—plastic nanoparticles that can encapsulate drugs. Image courtesy of UNSW Sydney.