New Hydrogel Doesn't Dry Out - Ideal for Medical Applications

Made mostly of water, hydrogels are stretchy and absorbent until they inevitably dry out. Now engineers at MIT have found a way to prevent hydrogels from dehydrating, with a technique that could lead to longer-lasting contact lenses, stretchy microfluidic devices, flexible bioelectronics, and artificial skin. The engineers devised a method to robustly bind hydrogels to elastomers - elastic polymers such as rubber and silicone that are stretchy like hydrogels yet impervious to water. They found that coating hydrogels with a thin elastomer layer provided a water-trapping barrier that kept the hydrogel moist, flexible, and robust. The group took inspiration for its design from human skin, which is composed of an outer epidermis layer bonded to an underlying dermis layer. The epidermis acts as a shield, protecting the dermis and its network of nerves and capillaries, as well as the rest of the body's muscles and organs, from drying out.

Transcript

00:00:05 Hydrogels are a gelatin-like polymer material made mostly of water. They are stretchy and robust and in the case of a hydrogel developed by a team at MIT, they can be extremely sticky. They can be used for a variety of applications such as embedding electrical sensors within the hydrogel to create a "smart

00:00:23 bandage" or as a way to deliver drugs to a patient. However, much like anything made up of over 90 percent water, hydrogels will eventually dry out losing their flexibility. Now, the same team of researchers from MIT that developed a robust, sticky hydrogel has found a way to prevent hydrogels from

00:00:39 dehydrating with a technique that could lead to longer-lasting contact lenses, stretchy micro- fluidic devices, flexible bio- electronics and even artificial skin. Their method involves binding the hydrogels to elastomers, otherwise known as elastic polymers such as rubber and silicone. These elastomers

00:00:56 are stretchy like hydrogels yet impervious to water. They found that coating the hydrogels with a thin elastomer layer provided a water-trapping barrier that kept the hydrogel moist, flexible and robust. The researchers pulled inspiration from skin. More specifically the bond between the epidermis and the

00:01:12 dermis. Where the epidermis acts as a shield, protecting the dermis and its network of nerves and capillaries as well as the rest of the body's internal muscles and organs from drying out. Similarly with their hydrogel-elastomer hybrid the elastomer is the shield that protects the hydrogel and all

00:01:28 the components embedded within it, from drying out. Next, the group hopes to further test the hybrid material's potential in a number of applications including wearable electronics and on-demand drug-delivering bandages, as well as nondrying, circuit-embedded contact lenses.