Surface Coatings Could Help Medical Implant Function

While medical devices are a far cry from garage or warehouse floors, some interesting news come about this month regarding the possibility of surface coatings, the same substances used as floor coatings, being used to help the function of medical implants.

Throughout the years, many ideas for medical implants have been introduced. Of those include devices that can release insulin or any other drug when the body would have an immediate need or small devices that monitor bodily function. The issue, however, has been that small implants tend to be recognized by the body’s immune system as an invader. The cells then encapsulate the device and render it not functional.

This has resulted in some experimentation, which involves polymers that are biocompatible that can coat the sensors of an implant so that the device is cloaked from the immune system. In other words, a polymer could put the device in stealth mode. Right now, researchers are looking for any surface coatings that can be placed on the device so that the body is unable to sense it.

Recent research has shown that thin layers of block copolymers that coat the tiny sensors of a device that detects the amount of carbon dioxide, blood glucose, and serum pH levels are not sensed by the body. The coating uses a multi-layer concept that includes a hermetic sealing layer, which is a chemically inert innermost diffusion barrier for humidity and ions.

Implanted just under the skin, the coated sensor data could be wirelessly monitored so that it could control an insulin pump or monitor various bodily functions to give a doctor better ideas of how to treat their patients.

With so many different types of polymers and combinations that can make biocompatible coatings, it seems that more implants will be developed that won’t be rejected by the body. Thus far, there are retinal devices coated with biocompatible coatings and the coatings have kept the devices from being rejected by the body. Much of this research and these efforts to create such devices began in the 1980s.

Lastly, all of the polymers that are being considered or are already used lend themselves to drug delivery due to their chemical nature.