Melanoma is a type of skin cancer that is often caused by too much sun exposure. Conventional melanoma therapies, including chemotherapy and radiotherapy, suffer from the toxicity and side effects of repeated treatments due to the aggressive and recurrent nature of melanoma cells.
Microneedles offer pain-free alternative to hypodermic jabs
Less-invasive topical chemotherapies that use polymeric microneedles have emerged, but according to the team’s paper published in ACS Nano, the sustained and long-lasting release of drug cargos remains challenging.
"We developed a novel wearable patch with fully miniaturised needles, enabling unobtrusive drug delivery through the skin for the management of skin cancers," said Chi Hwan Lee, a Purdue assistant professor of biomedical engineering and mechanical engineering. "Uniquely, this patch is fully dissolvable by body fluids in a programmable manner such that the patch substrate is dissolved within one minute after the introduction of needles into the skin, followed by gradual dissolution of the silicon needles inside the tissues within several months."
Lee said this gradual slow dissolution of the silicon nanoneedles allows for long-lasting and sustainable delivery of cancer therapeutics.
"The uniqueness of our technology arises from the fact that we used extremely small but long-lasting silicon nanoneedles with sharpened angular tips that are easy for their penetration into the skin in a painless and minimally invasive manner," Lee said in a statement.
The Purdue team developed bioresorbable silicon nanoneedles that are built on a thin, flexible and water-soluble medical film. The water-soluble film serves as a temporary holder that conforms with the surface of the skin during the insertion of the nanoneedles, followed by rapid, complete dissolution within a minute.
The surface of the nanoneedles is configured with nanoscale pores and provides a large drug loading capacity comparable to those using conventional microneedles.
Five ways to prepare for your first day
If I may add my own personal Tip No. 6 it goes something like this: From time to time a more senior member of staff will start explaining something...