Anticlotting Medical Device : Inspired By Pitcher Plant

Technology Inspired By Nature : New Medical Device

Dialysis and implanted arteries widely used in medical industry to keep people alive. The major concern with these devices are blood clotting and infection due to adhered pathogens. Clotting of blood was  handled by treating blood with anticlotinng agents like Heparin. But this method have its own risk;by interfering with clotting, they can cause potentially deadly bleeding.

The New Dialysis Device

Recently, researchers at the Wyss Institute for Biologically Inspired Engineering at Harvard University looked to the carnivorous pitcher plant for guidance. The plant’s structure includes wells with surfaces too slippery for insects to crawl out of. Those surfaces inspired the development of a coating so slippery that it prevents blood and bacteria from sticking.

The team tested the coating on the interiors of tubes and catheters attached to pigs. They demonstrated that the coating did not degrade, and that blood kept flowing without clotting, for eight hours. Blood usually starts to clot in tubes in an hour. The study is in the journal Nature Biotechnology. [Daniel C. Leslie et al, A bioinspired omniphobic surface coating on medical devices prevents thrombosis and biofouling]

The researchers also tested whether a gecko could latch onto the coating with its notoriously sticky footpads. But not even the gecko could get a grip. 

Liquid-infused, Porous Surface (SLIPS) approach

SLIPS was inspired by the Nepenthes pitcher plant, which uses a layer of liquid water to create a low friction surface that prevents attachment of insects. The SLIPS technology creates omniphobic slippery surfaces by infiltrating porous or roughened substrates with various liquid perfluorocarbons (LPs) that prevent adhesion to the underlying substrate through formation of a stably immobilized, molecularly smooth, liquid overlayer. However, existing medical-grade materials, such as polycarbonate, polysulfone and polyvinyl chloride (PVC), have highly smooth surfaces. Thus, to create nonadhesive, antithrombogenic surfaces that might be useful for clinical medicine in the near-term, we set out to modify the SLIPS technology so that it can be applied to these smooth surfaces. This was accomplished by covalently binding a flexible molecular perfluorocarbon layer, or tethered perfluorocarbon (TP), on the material surface and then coating it with a mobile layer of an LP (perfluorodecalin) that has been used extensively in medicine for applications such as liquid ventilation, ophthalmic surgery and as an US Food and Drug Administration (FDA)-approved blood substitute.