Purdue University innovators have created a novel wearable patch to help address the painful size of the microneedles and the rapidly dissolving behaviour of polymers used in treatment of melanoma.
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. Less invasive topical chemotherapies have emerged as alternatives, but their widespread uses have been hindered by both the painful size of the microneedles and the rapidly dissolving behaviour of polymers used in the treatments.
“We developed a novel wearable patch with fully miniaturized 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.
The Purdue innovators developed a novel design of 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 can be conformably interfaced with the soft, curvilinear 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. Lee said the nanoneedles could deliver the chemotherapeutic drugs to target melanoma sites in a sustainable manner. The silicon nanoneedles are biocompatible and dissolvable in tissue fluids, such that they can be completely resorbed in the body over months in a harmless manner.
This work is supported by the Air Force Office of Scientific Research (AFOSR: FA2386-18-1-40171).
Lee said he started working on this type of technology after seeing his daughter express fearful thoughts about needles when receiving vaccinations.
The team worked with the Purdue Research Foundation Office of Technology Commercialisation to patent this technology. The office recently moved into the Convergence Centre for Innovation and Collaboration in Discovery Park District, adjacent to the Purdue campus.
The researchers are looking for partners to continue developing their technology. For more information on licensing and other opportunities, contact Patrick Finnerty of OTC at email@example.com and mention track code 2020-LEE-68893.
Lee’s team worked with Yoon Yeo from Purdue’s College of Pharmacy and Dong Rip Kim at Hanyang University in South Korea to develop and test the technology.
Conventional melanoma therapies suffer from the toxicity and side effects of repeated treatments due to the aggressive and recurrent nature of melanoma cells. Less-invasive topical chemotherapies by utilizing polymeric microneedles have emerged as an alternative, but the sustained, long-lasting release of drug cargos remains challenging. In addition, the size of the microneedles is relatively bulky for the small, curvilinear, and exceptionally sensitive cornea for the treatment of ocular melanoma. Here, we report a design of bioresorbable, miniaturized porous-silicon (p-Si) needles with covalently linked drug cargos at doses comparable to those of conventional polymeric microneedles. The p-Si needles are built on a water-soluble film as a temporary flexible holder that can be intimately interfaced with the irregular surface of living tissues, followed by complete dissolution with saline solution within 1 min. Consequently, the p-Si needles remain embedded inside tissues and then undergo gradual degradation, allowing for sustained release of the drug cargos. Its utility in unobtrusive topical delivery of chemotherapy with minimal side effects is demonstrated in a murine melanoma model.
Hyungjun Kim, Heung Soo Lee, Yale Jeon, Woohyun Park, Yue Zhang, Bongjoong Kim, Hanmin Jang, Baoxing Xu, Yoon Yeo, Dong Rip Kim and Chi Hwan Lee
Purdue University material
ACS Nano abstract