by Joel Harrison
30. September 2010 15:13
Because slow and steady delivery of medicines to the eye is beneficial in the treatment of various ocular diseases, scientists have been studying ways of modifying contact lenses so that they could perform this function effectively. Here, numerous factors, such as the properties of the lens surface, water content or thickness, have to be taken into account, which makes the issue a complex one.
Researchers have already come up with different forms of drug-dispensing contact lenses, which use different approaches to the problem. One of them is to put liposomes containing medications on the surface of the contact lens and disperse them in the matrix of the lens, achieving release time of up to seven days. Another is to use a PLGA polymer film, which can store large quantities of medications and release them slowly for as long as 30 days, or vitamin E, which increases the release time of certain drugs of up to 100 times.
These experimental methods (and several others) show a lot of promise, though they must be significantly modified before a clinically reliable contact lens drug delivery system becomes a viable option for eye care practitioners.
Subscribe