When patients undergo a medical procedure, they are at risk of exposure to bacteria and infection when any foreign object enters their body. To ensure patients’ safety, the FDA requires that medical devices be protected with an antimicrobial and hypoallergenic coating. Common examples of coated devices include surgical instruments, catheters, stents, needles, probes, implants, and cardiac-assist devices. Although there are several types of coatings available for medical equipment, parylene is the coating of choice for the following four reasons.
- Parylene Is Safe
One of the most important characteristics of a coating for medical devices is biocompatibility, according to https://pctconformalcoating.com/. If a coating is biocompatible, it can enter the body safely without causing irritation, inflammation, or any other negative reaction. Research has demonstrated that parylene is a completely non-toxic substance that is compatible with cell growth and blood coagulation. It’s also a highly stable material, meaning it doesn’t react to other chemicals. Furthermore, parylene creates an impermeable coating, free of pinholes, that further protects the patient from accidental exposure to contamination.
- Parylene Is Smooth And Flexible
Another benefit of parylene is its smoothness, or dry lubricity. A parylene coating provides an elastic, low-friction surface. When patients undergo an invasive procedure, such as catheterization or laparoscopic surgery, a smooth coating minimizes damage to the skin and keeps the patient from experiencing unnecessary pain. Another valuable feature of the coating is its elasticity. Because the coating is made of long polymers, it can stretch and bend and then easily regain its original shape. Thus, parylene is the ideal coating for tubing, catheters, and other flexible devices.
- Parylene Can Be Sterilized
While parylene is naturally resistant to bacteria and other microbes, parylene-coated medical devices must still undergo a sterilization procedure before they can be used on a patient. Through sterilization, all life forms are removed from a surface to protect the patient from any possible contaminant. Parylene is an ideal medical coating because it can withstand the high heat and chemical methods used to sterilize medical equipment. For example, parylene coatings are compatible with electron beam sterilization, gamma radiation, ethylene oxide, autoclaving, and other common sterilization methods.
- Parylene Resists Corrosion
Not only does a parylene coating protect the patient from the medical device, but it also protects the device from the patient. Bodily fluids are corrosive to metals, and medical implants, in particular, are at risk of breaking down. With constant exposure to blood and extra-cellular fluids, the metal parts of implants such as artificial joints and pacemakers may become pitted and cracked, and their crevices may deepen. A parylene coating creates a chemically resistant barrier that conforms exactly to the surface of the device. When an implanted device begins to corrode, not only do patients experience an inflammatory reaction, but the performance of the implant will also degrade.
The FDA has approved parylene as a Class VI plastic, meaning it has met the highest safety standards of the United States Pharmacopeia (USP). Class VI coatings are highly biocompatible, non-toxic, and safe for use in medical applications. Some other benefits of parylene include its light weight, chemical stability, and uniformity. As the coating is applied as a vapor rather than a liquid, it doesn’t have a curing phase. All of these factors make parylene coatings the ideal choice for medical devices of all kinds.