Researchers have developed a fast-acting skin patch that can deliver medication to treat melanoma in one minute. The research was presented at the American Chemical Society (ACS) Fall 2019 National Meeting and Exposition. Not only does this research have promising implications for an effective melanoma vaccine, but the technology could also be applied to other vaccinations for infectious diseases too.
Dangerous skin cancer
Approximately 96,480 people will be diagnose with melanoma in the US in 2019; according to estimates made by the American Cancer Society; with rates having on the rise for thirty years. The American Academy of Dermatology states that 20 Americans die every day from this dangerous type of skin cancer. The researchers aim to reduce the number of patients who stop taking melanoma medication because it requires a long application time or involves the use of syringes; which can be painful and inconvenient.
Topical ointments apply to the skin are already available; but the medication can only be absorb to a certain depth. The new microneedle patches develop by scientists at the Massachusetts Institute of Technology (MIT) are able to efficiently deliver an effective amount of medication in a pain-free, convenient way. The patches are make with a layer-by-layer (LbL) coating method. Each layer of the patch is cover in molecules with alternating positive and negative charges.
In order to get a strong layer of medication on the patch’s surface; each layer of the patch needs to be firmly attach to one another and to the microneedle. However, Yanpu He explain that the attraction between the layers of positive and negative molecules “makes the entire film very sticky. Past methods, which have retain this ‘sticky’ nature, can take up to 90 minutes for a sufficient amount of drug to leave the patch and enter the skin.”
Immune activation of human skin
This means that, because the film is held together firmly the solubility of the base layer of the patch is decrease; as a result hampering the implantation of the medicate films into the skin. In order to rectify this problem; also significantly reduce the amount of time it takes for the drug to be administer Paula T. Hammond, PhD, with He, another graduate student Celestine Hong, and a team of MIT colleagues; produce a new, pH-responsive polymer made in two parts:
The sticky positive to negative layers are still need to make the LbL film; but the newly design patch rapidly changes to repelling negative-negative-negative layers when it is in contact with the skin. In their experiments, the researchers found that their microneedle patches produce nine times the antibody response when compare to intramuscular injections; also 160 times the antibody response compare to subcutaneous injections. Immune activation was also see in samples of human skin.
Hammond was enthusiastic about the patch’s application in treating infectious diseases. Our patch technology could be use to deliver vaccines to combat different infectious diseases. But we are excite by the possibility that the patch is another tool in the oncologist’s arsenal against cancer, specifically melanoma.” “We are using low-cost chemistry and a simple fabrication scheme to transform vaccination,” Hammond continued. “Ultimately, we want to get a device approve and on the market.”