Injectable sponge stars and hearts deliver drugs
Drug delivery can take any shape you like, from squares to stars and hearts to circles. This is according to bioengineers at Harvard University, who have created compressible bioscaffolds that can squeeze through syringes and pop back into shape once they are inside the body. The research was published in the Proceedings of the National Academy of Sciences.
The shape-memory sponges are made from alginate, derived from seaweed, and are threaded with networks of pores created during a process known as cryogelation. The pores can deliver large- or small-molecule drugs, releasing them over long periods as the gel biodegrades.
The scaffolds, which can be any size or shape, can also be loaded with stem cells to deliver biomolecules or regenerate tissues, or with immune cells in immunotherapy. The cells have shown enhanced survival, higher local retention, and extended engraftment at the injection site compared with a standard injection technique.
"What we've created is a three-dimensional structure that you could use to influence the cells in the tissue surrounding it and perhaps promote tissue formation," explains principal investigator David J. Mooney at the Harvard School of Engineering and Applied Sciences.
The gels could also have potential to bulk out missing tissue, as specifically shaped tissue patches, or as dermal filler in cosmetics. The university has filed patent applications and is looking for partners.
Hydrogel foams can deliver drugs for 6 months