Scientists from Massachusetts Institute of Technology have designed a new type hydrogel for medical use. This gel is designed to deliver needed drugs to a specific place in patient’s body and could act as a long-term drug depot, releasing its payload over a specified time period. But most important feature of this gel is self-healing properties that mean it can be injected through a syringe.
Similar hydrogels have been in use for quite some time now (for example, to make soft contact lenses), but they were made by forming irreversible chemical linkages between polymers. That meant that shape of formed hydrogel body could not be easily altered, therefore surgery was needed in order to implant such gel. Furthermore, former methods of forming such hydrogels required complex biochemical processes.
New gel is much more flexible, since polymer chain forms relatively weak bonds that could be broken by altering shape of the gel. For example, this may happen when squeezing the gel through syringe. Then, when forces are released, gel returns to its previous shape and reattaches broken bonds between polymers, effectively healing itself. Moreover, it is also made from rather simple materials, which do not require any advanced chemical functionalization.
This new gel consists of two components: nanoparticles made of polymers entwined within strands of another polymer, such as cellulose. It means that gel can carry two different drugs at the same time. For example, core of the nanoparticles is ideal for carrying hydrophobic small-molecule drugs (such as chemotherapy drugs) while the polymers can carry hydrophilic molecules such as proteins, including antibodies and growth factors. Experimentation with mice already proved that both self-healing properties and two drug delivery works as scientists have predicted.
Advantages of such technology are many. For example, other injected drugs immediately disperse throughout the body, while gel stays in place where it was planted, affecting intended target. Different drugs can be released at different times, providing possibility to precisely plan the treatment. Technology can be used for different applications.
New gel could be used to treat cancer patients. Since removing the tumour leaves a cavity, the gel can be tailored to fit exactly in the created void and keep releasing drugs to treat tissues around it. Macular degeneration patients are currently treated with injections into the eye, while gel would provide a possibility to reduce frequency of these injections. It could also be used for heart disease treatment, as well as treatment of other diseases.
New nanogel should provide new possibilities for safer, less damaging treatment tailored specifically to each patient’s condition. Relatively simple production of the gel, its self-healing properties and possibility to deliver two different drugs releasing them at different times suggests new approaches in treatment of many diseases, even though it will take some time for this technology to be fully approved.